Replace labels with authoritative V10 task prompts

README.md

@@ -4,4 +4,4 @@ pretty_name: CADBench Hard Tasks
 
 # CADBench Hard Tasks
 
-43 V10 tasks above medium difficulty: 35 hard and 8 expert. Each folder contains a concise task and its authoritative Fusion reference.
+43 V10 tasks above medium difficulty: 35 hard and 8 expert. Each folder contains the complete, unabridged V10 task prompt and its authoritative Fusion reference.

tasks/j4_ch1_dogbone_base/task.md

@@ -1,3 +1,63 @@
 # Build the disc base and dogbone link
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 5 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 5
+
+In the empty millimetre design that is already open (do not create a new document), create and finish one fully constrained sketch on the YZ origin plane. Draw exactly one circle with its center coincident with the sketch origin at global (0, 0, 0) and set its diameter to 55 mm. Finish the sketch without creating a solid.
+
+### Stage 2 of 5
+
+Continuing from the previous stage, using the Ø55 mm circle sketch, extrude its single circular profile 5 mm in the global positive-X direction so the disc spans X = 0 to X = 5. Use a one-sided extrusion, 0° taper, and New Body. Do not add any other feature.
+
+### Stage 3 of 5
+
+Continuing from the previous stage, using the Ø55 × 5 mm disc, create exactly one construction plane using the Offset method with the XY origin plane as reference and an offset distance of −27.5 mm, so the plane lies at global Z = −27.5. Do not create a sketch or solid feature.
+
+### Stage 4 of 5
+
+Continuing from the previous stage, using the disc and offset plane, create a sketch on the offset plane at Z = −27.5 containing a closed dogbone/link profile whose axis runs along the global X axis at Y = 0, built in the following sub-steps. Finish the sketch without extruding it.
+
+#### Step 4.1 — Link Outline and Anchor Dimensions
+
+*(video 235.8–355 s)*
+
+Create the sketch on the plane at Z = −27.5. Draw the link outline segments along the X axis and apply the anchor dimensions: 150 mm overall length from the origin to the far end at X = −150, 23 mm from the origin to the left circle center at (−23, 0), and 40 mm for the right end radius about (−110, 0). An auxiliary 27.5 mm dimension is also placed.
+
+#### Step 4.2 — End Circles
+
+*(video 355–448 s)*
+
+Draw the two end circles of the link: the left circle centered at global (−23, 0) over the disc, whose diameter is left undimensioned and resolves to approximately Ø71.7, and the right circle of radius 40 mm centered at global (−110, 0) at the far end.
+
+#### Step 4.3 — Upper Tangent Arc
+
+*(video 448–490 s)*
+
+Using the Three-Point Arc tool, draw one arc of radius 85 mm along the positive-Y side connecting the two ends, and dimension it to R85. Its center resolves to global (−60.64, +114.84).
+
+#### Step 4.4 — Tangent Constraint and Mirror
+
+*(video 537–572 s)*
+
+Apply the tangent constraint, then mirror the R85 arc across the link axis with the sketch Mirror command so a matching arc (center (−60.64, −114.84)) closes the negative-Y side.
+
+#### Step 4.5 — Cleanup and Finish
+
+*(video 585–762.9 s)*
+
+Delete the leftover arc segments so only the closed dogbone boundary remains, and finish the sketch. The finished profile is bounded by X = −150 to X ≈ +12.9, with the R40 right end at (−110, 0) and the ~Ø71.7 left end at (−23, 0).
+
+### Stage 5 of 5
+
+Continuing from the previous stage, using the dogbone sketch, select all 6 profiles and extrude them together 15 mm in the global positive-Z direction, so the plate spans Z = −27.5 to Z = −12.5. Use a one-sided extrusion, 0° taper, and Join. Do not add any other feature.
+
+End state across all stages: exactly 2 new sketches, 2 new extrusion or revolve features, 1 construction plane feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/j4_ch2_plateau_keyhole/task.md

@@ -1,3 +1,37 @@
 # Build the offset plateaus and keyhole cut
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 6 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 6
+
+Starting from the supplied plate, create a sketch on its lower face at Z = −27.5. Chain-select the outer plate contour and offset it 2.5 mm inward, producing an inner closed loop and two profiles. Finish the sketch without extruding it.
+
+### Stage 2 of 6
+
+Continuing from the previous stage, using the offset sketch, extrude only the inner region by 1 mm in the global negative-Z direction, to Z = −28.5. Use a one-sided extrusion, 0° taper, and Join. Do not extrude the outer rim region and do not add any other feature.
+
+### Stage 3 of 6
+
+Continuing from the previous stage, using the 1 mm plateau, create a sketch on its face at Z = −28.5 and offset the boundary 2.5 mm outward using a −2.5 mm sketch offset. Finish the sketch without extruding it.
+
+### Stage 4 of 6
+
+Continuing from the previous stage, using the stacked plateau, select the plateau face and extrude it 6.5 mm in the global negative-Z direction, to Z = −40, with a taper angle of −65° and Join. Do not add any other feature.
+
+### Stage 5 of 6
+
+Continuing from the previous stage, using the body, create a sketch on the tapered plateau face at Z = −40 containing a keyhole slot profile: one Ø8 mm circle and connecting straight segments dimensioned 5mm going horizontally into the negative X-direction from the top and bottom of the circle. Connect the horizontal lines with a vertical line of length 8mm. The finished sketch must contain two profiles. Finish the sketch without cutting it.
+
+### Stage 6 of 6
+
+Continuing from the previous stage, using the keyhole sketch, select both keyhole profiles and extrude-cut them 6.5 mm into the material (from Z = −40 toward positive Z, recess floor at Z = −33.5) using a one-sided −6.5 mm distance with 0° taper. Use a fixed Distance extent, not Through All, and add no other feature.
+
+End state across all stages: exactly 3 new sketches, 4 new extrusion or revolve features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/j4_ch3_bolt_patterns/task.md

@@ -1,3 +1,53 @@
 # Build the bolt details and edge patterns
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 10 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 10
+
+Starting from the supplied keyhole recess, create a sketch on the recess floor at Z = −33.5. Draw one Ø2.5 mm circle centered on the 8mm circle midpoint and offset it 1 mm outward, producing a concentric Ø4.5 mm circle and an annular profile. Finish the sketch without extruding it.
+
+### Stage 2 of 10
+
+Continuing from the previous stage, using the two-circle sketch, select only the annular region between the Ø2.5 mm and Ø4.5 mm circles and extrude it 0.5 mm in the global negative-Z direction, to Z = −34. Use a one-sided extrusion, 0° taper, and Join. Leave the inner disk unextruded and add no other feature.
+
+### Stage 3 of 10
+
+Continuing from the previous stage, using the single keyhole-and-annulus detail, create a Circular Pattern of the two features — the keyhole cut and the annulus extrusion — around the global Z axis through (−110, 0). Use Full distribution over 360°, quantity 7, Identical compute type, and suppress the 2 left-most    instances so 5 remain, centered at (−146, 0), (−132.45, ±28.15) and (−101.99, ±35.10). Pattern the features, not sketch geometry or faces, and add no other feature.
+
+### Stage 4 of 10
+
+Continuing from the previous stage, using the patterned details, create a Pattern on Path. Set Object Type to Faces and select the 8 faces of the boss detail at (−101.99, +35.10), select the positive-Y wavy plate edge as the path, and use quantity 4, distance 89 mm, start point 0, Extent distribution, One Direction, and Path Direction orientation. The added instances land at (−72.70, 26.41), (−41.73, 27.61) and (−15.16, 30.90). Add no other feature.
+
+### Stage 5 of 10
+
+Continuing from the previous stage, using the body, create a sketch on the plate top face at Z = −12.5 containing one straight line across the part that isolates the disc-end region (X greater than −34) as a closed profile against the existing plate boundary. Finish the sketch without extruding it.
+
+### Stage 6 of 10
+
+Continuing from the previous stage, using the body, create exactly one construction plane using the Midplane method between the two parallel flat faces at Z = −27.5 and Z = +27.5 (55 mm apart), giving a plane at Z = 0. Do not create a sketch or solid feature.
+
+### Stage 7 of 10
+
+Continuing from the previous stage, using the body, create a sketch on the plate top face at Z = −12.5 containing one straight line across the part that isolates the disc-end region (X greater than −34) as a closed profile against the existing plate boundary. Finish the sketch without extruding it.
+
+### Stage 8 of 10
+
+Continuing from the previous stage, using the patterned details, create a Pattern on Path. Set Object Type to Faces and select the 8 faces of the boss detail at (−101.99, +35.10), select the positive-Y wavy plate edge as the path, and use quantity 4, distance 89 mm, start point 0, Extent distribution, One Direction, and Path Direction orientation. The added instances land at (−72.70, 26.41), (−41.73, 27.61) and (−15.16, 30.90). Add no other feature.
+
+### Stage 9 of 10
+
+Continuing from the previous stage, using the body, create a sketch on the plate top face at Z = −12.5 containing one straight line across the part that isolates the disc-end region (X greater than −34) as a closed profile against the existing plate boundary. Finish the sketch without extruding it.
+
+### Stage 10 of 10
+
+Continuing from the previous stage, using the boundary sketch, select the single disc-end region and extrude it 40 mm in the global positive-Z direction, so the block spans Z = −12.5 to Z = +27.5. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+End state across all stages: exactly 4 new sketches, 2 new extrusion or revolve features, 1 circular pattern feature, 2 path pattern features, 1 construction plane feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/j4_ch4_endblock_mirrors/task.md

@@ -1,3 +1,45 @@
 # Build the end block and mirror the features
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 7 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 7
+
+Starting from the supplied body, create exactly one construction plane using the Midplane method between the two parallel flat faces at Z = −27.5 and Z = +27.5 (55 mm apart), giving a plane at Z = 0. Do not create a sketch or solid feature.
+
+### Stage 2 of 7
+
+Continuing from the previous stage, using the mirrored body, create a second Mirror feature with Object Type set to Faces. Select the 2 counterbore faces on the wavy edge and the same midplane as the mirror plane. Add no other feature.
+
+### Stage 3 of 7
+
+Continuing from the previous stage, using the body, create a sketch on the disc outer face at X = +5. Draw exactly one Ø30 mm circle centered on the global X axis at (5, 0, 0). Finish the sketch without extruding it.
+
+### Stage 4 of 7
+
+Continuing from the previous stage, using the Ø30 mm circle sketch, extrude its single profile by 20 mm in the global positive-X direction, so the stub spans X = 5 to X = 25. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 5 of 7
+
+Continuing from the previous stage, using the body, create a sketch on the disc outer face at X = +5. Draw exactly one Ø30 mm circle centered on the global X axis at (5, 0, 0). Finish the sketch without extruding it.
+
+### Stage 6 of 7
+
+Continuing from the previous stage, using the body, create exactly one construction plane using the Midplane method between the two clevis inner faces at Z = −12.5 and Z = +12.5 (25 mm apart), giving a plane at Z = 0. Do not create a sketch or solid feature.
+
+### Stage 7 of 7
+
+Continuing from the previous stage, using the body and clevis midplane, create a Mirror feature with Object Type set to Features. Select the single Ø20 mm hole-cut feature and the clevis midplane (Z = 0) as the mirror plane, with Identical compute type, so a matching hole spans Z = +12.5 to Z = +22.5 in the opposite clevis face. This completes the Jaw_4 geometry: 31 timeline features, exactly one body, bounding box X −149.8..25, Y ±39.7, Z ±40. Add no other feature.
+
+---
+
+## Part 2 — Jaw_5 (Tasks 29–52)
+
+End state across all stages: exactly 2 new sketches, 2 new extrusion or revolve features, 3 mirror features, 2 construction plane features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/j4_ch5_full/task.md

@@ -1,3 +1,159 @@
 # Build the complete Jaw_4 link from a blank design
 
-Expert · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 28 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 28
+
+In the empty millimetre design that is already open (do not create a new document), create and finish one fully constrained sketch on the YZ origin plane. Draw exactly one circle with its center coincident with the sketch origin at global (0, 0, 0) and set its diameter to 55 mm. Finish the sketch without creating a solid.
+
+### Stage 2 of 28
+
+Continuing from the previous stage, using the Ø55 mm circle sketch, extrude its single circular profile 5 mm in the global positive-X direction so the disc spans X = 0 to X = 5. Use a one-sided extrusion, 0° taper, and New Body. Do not add any other feature.
+
+### Stage 3 of 28
+
+Continuing from the previous stage, using the Ø55 × 5 mm disc, create exactly one construction plane using the Offset method with the XY origin plane as reference and an offset distance of −27.5 mm, so the plane lies at global Z = −27.5. Do not create a sketch or solid feature.
+
+### Stage 4 of 28
+
+Continuing from the previous stage, using the disc and offset plane, create a sketch on the offset plane at Z = −27.5 containing a closed dogbone/link profile whose axis runs along the global X axis at Y = 0, built in the following sub-steps. Finish the sketch without extruding it.
+
+#### Step 4.1 — Link Outline and Anchor Dimensions
+
+*(video 235.8–355 s)*
+
+Create the sketch on the plane at Z = −27.5. Draw the link outline segments along the X axis and apply the anchor dimensions: 150 mm overall length from the origin to the far end at X = −150, 23 mm from the origin to the left circle center at (−23, 0), and 40 mm for the right end radius about (−110, 0). An auxiliary 27.5 mm dimension is also placed.
+
+#### Step 4.2 — End Circles
+
+*(video 355–448 s)*
+
+Draw the two end circles of the link: the left circle centered at global (−23, 0) over the disc, whose diameter is left undimensioned and resolves to approximately Ø71.7, and the right circle of radius 40 mm centered at global (−110, 0) at the far end.
+
+#### Step 4.3 — Upper Tangent Arc
+
+*(video 448–490 s)*
+
+Using the Three-Point Arc tool, draw one arc of radius 85 mm along the positive-Y side connecting the two ends, and dimension it to R85. Its center resolves to global (−60.64, +114.84).
+
+#### Step 4.4 — Tangent Constraint and Mirror
+
+*(video 537–572 s)*
+
+Apply the tangent constraint, then mirror the R85 arc across the link axis with the sketch Mirror command so a matching arc (center (−60.64, −114.84)) closes the negative-Y side.
+
+#### Step 4.5 — Cleanup and Finish
+
+*(video 585–762.9 s)*
+
+Delete the leftover arc segments so only the closed dogbone boundary remains, and finish the sketch. The finished profile is bounded by X = −150 to X ≈ +12.9, with the R40 right end at (−110, 0) and the ~Ø71.7 left end at (−23, 0).
+
+### Stage 5 of 28
+
+Continuing from the previous stage, using the dogbone sketch, select all 6 profiles and extrude them together 15 mm in the global positive-Z direction, so the plate spans Z = −27.5 to Z = −12.5. Use a one-sided extrusion, 0° taper, and Join. Do not add any other feature.
+
+### Stage 6 of 28
+
+Continuing from the previous stage, using the plate, create a sketch on its lower face at Z = −27.5. Chain-select the outer plate contour and offset it 2.5 mm inward, producing an inner closed loop and two profiles. Finish the sketch without extruding it.
+
+### Stage 7 of 28
+
+Continuing from the previous stage, using the offset sketch, extrude only the inner region by 1 mm in the global negative-Z direction, to Z = −28.5. Use a one-sided extrusion, 0° taper, and Join. Do not extrude the outer rim region and do not add any other feature.
+
+### Stage 8 of 28
+
+Continuing from the previous stage, using the 1 mm plateau, create a sketch on its face at Z = −28.5 and offset the boundary 2.5 mm outward using a −2.5 mm sketch offset. Finish the sketch without extruding it.
+
+### Stage 9 of 28
+
+Continuing from the previous stage, using the stacked plateau, select the plateau face and extrude it 6.5 mm in the global negative-Z direction, to Z = −40, with a taper angle of −65° and Join. Do not add any other feature.
+
+### Stage 10 of 28
+
+Continuing from the previous stage, using the body, create a sketch on the tapered plateau face at Z = −40 containing a keyhole slot profile: one Ø8 mm circle and connecting straight segments dimensioned 5mm going horizontally into the negative X-direction from the top and bottom of the circle. Connect the horizontal lines with a vertical line of length 8mm. The finished sketch must contain two profiles. Finish the sketch without cutting it.
+
+### Stage 11 of 28
+
+Continuing from the previous stage, using the keyhole sketch, select both keyhole profiles and extrude-cut them 6.5 mm into the material (from Z = −40 toward positive Z, recess floor at Z = −33.5) using a one-sided −6.5 mm distance with 0° taper. Use a fixed Distance extent, not Through All, and add no other feature.
+
+### Stage 12 of 28
+
+Continuing from the previous stage, using the keyhole recess, create a sketch on the recess floor at Z = −33.5. Draw one Ø2.5 mm circle centered on the 8mm circle midpoint and offset it 1 mm outward, producing a concentric Ø4.5 mm circle and an annular profile. Finish the sketch without extruding it.
+
+### Stage 13 of 28
+
+Continuing from the previous stage, using the two-circle sketch, select only the annular region between the Ø2.5 mm and Ø4.5 mm circles and extrude it 0.5 mm in the global negative-Z direction, to Z = −34. Use a one-sided extrusion, 0° taper, and Join. Leave the inner disk unextruded and add no other feature.
+
+### Stage 14 of 28
+
+Continuing from the previous stage, using the single keyhole-and-annulus detail, create a Circular Pattern of the two features — the keyhole cut and the annulus extrusion — around the global Z axis through (−110, 0). Use Full distribution over 360°, quantity 7, Identical compute type, and suppress the 2 left-most    instances so 5 remain, centered at (−146, 0), (−132.45, ±28.15) and (−101.99, ±35.10). Pattern the features, not sketch geometry or faces, and add no other feature.
+
+### Stage 15 of 28
+
+Continuing from the previous stage, using the patterned details, create a Pattern on Path. Set Object Type to Faces and select the 8 faces of the boss detail at (−101.99, +35.10), select the positive-Y wavy plate edge as the path, and use quantity 4, distance 89 mm, start point 0, Extent distribution, One Direction, and Path Direction orientation. The added instances land at (−72.70, 26.41), (−41.73, 27.61) and (−15.16, 30.90). Add no other feature.
+
+### Stage 16 of 28
+
+Continuing from the previous stage, using the body, create a sketch on the plate top face at Z = −12.5 containing one straight line across the part that isolates the disc-end region (X greater than −34) as a closed profile against the existing plate boundary. Finish the sketch without extruding it.
+
+### Stage 17 of 28
+
+Continuing from the previous stage, using the body, create exactly one construction plane using the Midplane method between the two parallel flat faces at Z = −27.5 and Z = +27.5 (55 mm apart), giving a plane at Z = 0. Do not create a sketch or solid feature.
+
+### Stage 18 of 28
+
+Continuing from the previous stage, using the body, create a sketch on the plate top face at Z = −12.5 containing one straight line across the part that isolates the disc-end region (X greater than −34) as a closed profile against the existing plate boundary. Finish the sketch without extruding it.
+
+### Stage 19 of 28
+
+Continuing from the previous stage, using the patterned details, create a Pattern on Path. Set Object Type to Faces and select the 8 faces of the boss detail at (−101.99, +35.10), select the positive-Y wavy plate edge as the path, and use quantity 4, distance 89 mm, start point 0, Extent distribution, One Direction, and Path Direction orientation. The added instances land at (−72.70, 26.41), (−41.73, 27.61) and (−15.16, 30.90). Add no other feature.
+
+### Stage 20 of 28
+
+Continuing from the previous stage, using the body, create a sketch on the plate top face at Z = −12.5 containing one straight line across the part that isolates the disc-end region (X greater than −34) as a closed profile against the existing plate boundary. Finish the sketch without extruding it.
+
+### Stage 21 of 28
+
+Continuing from the previous stage, using the boundary sketch, select the single disc-end region and extrude it 40 mm in the global positive-Z direction, so the block spans Z = −12.5 to Z = +27.5. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 22 of 28
+
+Continuing from the previous stage, using the body, create exactly one construction plane using the Midplane method between the two parallel flat faces at Z = −27.5 and Z = +27.5 (55 mm apart), giving a plane at Z = 0. Do not create a sketch or solid feature.
+
+### Stage 23 of 28
+
+Continuing from the previous stage, using the mirrored body, create a second Mirror feature with Object Type set to Faces. Select the 2 counterbore faces on the wavy edge and the same midplane as the mirror plane. Add no other feature.
+
+### Stage 24 of 28
+
+Continuing from the previous stage, using the body, create a sketch on the disc outer face at X = +5. Draw exactly one Ø30 mm circle centered on the global X axis at (5, 0, 0). Finish the sketch without extruding it.
+
+### Stage 25 of 28
+
+Continuing from the previous stage, using the Ø30 mm circle sketch, extrude its single profile by 20 mm in the global positive-X direction, so the stub spans X = 5 to X = 25. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 26 of 28
+
+Continuing from the previous stage, using the body, create a sketch on the disc outer face at X = +5. Draw exactly one Ø30 mm circle centered on the global X axis at (5, 0, 0). Finish the sketch without extruding it.
+
+### Stage 27 of 28
+
+Continuing from the previous stage, using the body, create exactly one construction plane using the Midplane method between the two clevis inner faces at Z = −12.5 and Z = +12.5 (25 mm apart), giving a plane at Z = 0. Do not create a sketch or solid feature.
+
+### Stage 28 of 28
+
+Continuing from the previous stage, using the body and clevis midplane, create a Mirror feature with Object Type set to Features. Select the single Ø20 mm hole-cut feature and the clevis midplane (Z = 0) as the mirror plane, with Identical compute type, so a matching hole spans Z = +12.5 to Z = +22.5 in the opposite clevis face. This completes the Jaw_4 geometry: 31 timeline features, exactly one body, bounding box X −149.8..25, Y ±39.7, Z ±40. Add no other feature.
+
+---
+
+## Part 2 — Jaw_5 (Tasks 29–52)
+
+End state across all stages: exactly 11 new sketches, 10 new extrusion or revolve features, 1 circular pattern feature, 2 path pattern features, 3 mirror features, 4 construction plane features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/j5_ch1_revolve_core/task.md

@@ -1,3 +1,49 @@
 # Build the revolved disks and face steps
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 9 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 9
+
+In the empty millimetre design that is already open (do not create a new document), create and finish one fully constrained sketch on the XZ origin plane. Draw a closed profile whose axis edge lies on the global Z axis from Z = 0 to Z = 20: a 42 mm bottom edge at Z = 0 extending to X = 42, a 35 mm top edge at Z = 20 extending to X = 35, and the outer side closed by a tangent arc of R25 mm. Apply Fix constraints as needed. Finish the sketch without creating a solid.
+
+### Stage 2 of 9
+
+Continuing from the previous stage, using the trapezoid sketch, create a Revolve of its single profile, selecting the profile edge on the global Z axis as the revolve axis. Use Partial extent with a 360° angle, One Side direction, and New Body. The result is a disk of Ø84 spanning Z = 0 to Z = 20 with an R25 rounded rim. Add no other feature.
+
+### Stage 3 of 9
+
+Continuing from the previous stage, using the disk, create a sketch on its top face at Z = 20. Draw exactly one circle of Ø79 mm centered on the Z axis at (0, 0, 20). Finish the sketch without extruding it.
+
+### Stage 4 of 9
+
+Continuing from the previous stage, using the Ø79 mm circle sketch, extrude its single profile by 1 mm in the global positive-Z direction, to Z = 21. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 5 of 9
+
+Continuing from the previous stage, using the disk, create a sketch on its top face at Z = 20. Draw exactly one circle of Ø79 mm centered on the Z axis at (0, 0, 20). Finish the sketch without extruding it.
+
+### Stage 6 of 9
+
+Continuing from the previous stage, using the body, create a sketch on the XZ origin plane containing the profile of a second disk stacked above the first: height 20 mm, radial extents 42 mm and 40 mm, with the outer side closed by a tangent arc of R37 mm. The profile spans Z = 21 to Z = 41 against the existing step. Finish the sketch without creating a solid.
+
+### Stage 7 of 9
+
+Continuing from the previous stage, using the second profile sketch, create a Revolve of its single profile through 360° about the global Z axis with New Body, producing a second Ø84 disk spanning Z = 21 to Z = 41 with an R37 rounded rim, separated from the first disk by the recessed Ø79 step at Z = 20–21. Add no other feature.
+
+### Stage 8 of 9
+
+Continuing from the previous stage, using the twin-disk body, create a sketch on the second disk's top face at Z = 41. Draw exactly one circle of Ø82.5 mm centered on the Z axis. Finish the sketch without extruding it.
+
+### Stage 9 of 9
+
+Continuing from the previous stage, using the Ø82.5 mm circle sketch, extrude its single profile by 1 mm in the global positive-Z direction, to Z = 42. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+End state across all stages: exactly 5 new sketches, 4 new extrusion or revolve features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/j5_ch2_hub_details/task.md

@@ -1,3 +1,73 @@
 # Build the hub, bolt bosses, tang, and pins
 
-Expert · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 15 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 15
+
+Starting from the supplied body, hide the bodies in the browser and create a sketch on the lip face plane at Z = 42. Draw exactly one circle dimensioned to Ø84 mm centered on the Z axis. The finished sketch must yield two selectable profiles. Finish the sketch without extruding it.
+
+### Stage 2 of 15
+
+Continuing from the previous stage, using the Ø70 mm circle sketch, extrude its single profile by 3 mm in the global positive-Z direction, so the hub spans Z = 49 to Z = 52. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 3 of 15
+
+Continuing from the previous stage, using the body, create a sketch on the top disk face at Z = 49. Draw exactly one circle dimensioned to Ø70 mm centered on the Z axis. Finish the sketch without extruding it.
+
+### Stage 4 of 15
+
+Continuing from the previous stage, using the Ø70 mm circle sketch, extrude its single profile by 3 mm in the global positive-Z direction, so the hub spans Z = 49 to Z = 52. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 5 of 15
+
+Continuing from the previous stage, using the body, create a sketch on the top disk face at Z = 49. Draw exactly one circle dimensioned to Ø70 mm centered on the Z axis. Finish the sketch without extruding it.
+
+### Stage 6 of 15
+
+Continuing from the previous stage, using the bolt-boss sketch, select the annular region between the Ø3 mm and Ø4.5 mm circles — the radial line splits it into two half-ring profiles, so select both — and extrude it 1 mm in the global positive-Z direction, to Z = 50. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 7 of 15
+
+Continuing from the previous stage, using the single bolt-boss detail, create a Circular Pattern of that extrusion feature around the global Z axis. Use Full distribution over 360°, quantity 16, and Identical compute type, placing bosses every 22.5° on the Ø77 bolt circle (radius 38.5). Pattern the feature, not sketch geometry or faces, and add no other feature.
+
+### Stage 8 of 15
+
+Continuing from the previous stage, using the body, create a sketch on the bottom disk face at Z = 0. Draw a center rectangle with diagonals, centered on the origin, dimensioned 24 mm along X and 40 mm along Y (corners at X = ±12, Y = ±20). Finish the sketch without extruding it.
+
+### Stage 9 of 15
+
+Continuing from the previous stage, using the 24 × 40 mm rectangle sketch, extrude its single profile by 42 mm in the global negative-Z direction, so the tang spans Z = 0 to Z = −42. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 10 of 15
+
+Continuing from the previous stage, using the body, create a sketch on the tang side face at X = −12. Draw exactly one circle dimensioned to Ø40 mm centered at global (−12, 0, −42), the tang end. Finish the sketch without extruding it.
+
+### Stage 11 of 15
+
+Continuing from the previous stage, using the Ø40 mm circle sketch, extrude its single profile −24 mm through the tang (from X = −12 to X = +12) with 0° taper and Join, forming the rounded Ø40 knob at the tang end. Add no other feature.
+
+### Stage 12 of 15
+
+Continuing from the previous stage, using the body, create a sketch on the tang side face at X = −12. Draw exactly one circle dimensioned to Ø20 mm, placed near the knob center — its final center is at global (−12, 0, −40), 2 mm above the Ø40 knob center. Finish the sketch without extruding it.
+
+### Stage 13 of 15
+
+Continuing from the previous stage, using the Ø20 mm circle sketch, extrude its single profile by 10 mm in the global negative-X direction, so the pin spans X = −12 to X = −22. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 14 of 15
+
+Continuing from the previous stage, using the body, create a sketch on the hub face at Z = 52. Draw exactly one circle at the face center (0, 0, 52) and type its diameter as 20 mm. Finish the sketch without extruding it.
+
+### Stage 15 of 15
+
+Continuing from the previous stage, using the Ø20 mm circle sketch, extrude its single profile by 10 mm in the global positive-Z direction, so the stud spans Z = 52 to Z = 62. Use a one-sided extrusion, 0° taper, and Join. This completes the Jaw_5 geometry: 24 timeline features, one solid body, bounding box X ±42, Y ±37, Z −62..+62. Add no other feature.
+
+End state across all stages: exactly 7 new sketches, 7 new extrusion or revolve features, 1 circular pattern feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/j5_ch3_full/task.md

@@ -1,3 +1,109 @@
 # Build the complete Jaw_5 hub from a blank design
 
-Expert · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 24 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 24
+
+In the empty millimetre design that is already open (do not create a new document), create and finish one fully constrained sketch on the XZ origin plane. Draw a closed profile whose axis edge lies on the global Z axis from Z = 0 to Z = 20: a 42 mm bottom edge at Z = 0 extending to X = 42, a 35 mm top edge at Z = 20 extending to X = 35, and the outer side closed by a tangent arc of R25 mm. Apply Fix constraints as needed. Finish the sketch without creating a solid.
+
+### Stage 2 of 24
+
+Continuing from the previous stage, using the trapezoid sketch, create a Revolve of its single profile, selecting the profile edge on the global Z axis as the revolve axis. Use Partial extent with a 360° angle, One Side direction, and New Body. The result is a disk of Ø84 spanning Z = 0 to Z = 20 with an R25 rounded rim. Add no other feature.
+
+### Stage 3 of 24
+
+Continuing from the previous stage, using the disk, create a sketch on its top face at Z = 20. Draw exactly one circle of Ø79 mm centered on the Z axis at (0, 0, 20). Finish the sketch without extruding it.
+
+### Stage 4 of 24
+
+Continuing from the previous stage, using the Ø79 mm circle sketch, extrude its single profile by 1 mm in the global positive-Z direction, to Z = 21. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 5 of 24
+
+Continuing from the previous stage, using the disk, create a sketch on its top face at Z = 20. Draw exactly one circle of Ø79 mm centered on the Z axis at (0, 0, 20). Finish the sketch without extruding it.
+
+### Stage 6 of 24
+
+Continuing from the previous stage, using the body, create a sketch on the XZ origin plane containing the profile of a second disk stacked above the first: height 20 mm, radial extents 42 mm and 40 mm, with the outer side closed by a tangent arc of R37 mm. The profile spans Z = 21 to Z = 41 against the existing step. Finish the sketch without creating a solid.
+
+### Stage 7 of 24
+
+Continuing from the previous stage, using the second profile sketch, create a Revolve of its single profile through 360° about the global Z axis with New Body, producing a second Ø84 disk spanning Z = 21 to Z = 41 with an R37 rounded rim, separated from the first disk by the recessed Ø79 step at Z = 20–21. Add no other feature.
+
+### Stage 8 of 24
+
+Continuing from the previous stage, using the twin-disk body, create a sketch on the second disk's top face at Z = 41. Draw exactly one circle of Ø82.5 mm centered on the Z axis. Finish the sketch without extruding it.
+
+### Stage 9 of 24
+
+Continuing from the previous stage, using the Ø82.5 mm circle sketch, extrude its single profile by 1 mm in the global positive-Z direction, to Z = 42. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 10 of 24
+
+Continuing from the previous stage, using the body, hide the bodies in the browser and create a sketch on the lip face plane at Z = 42. Draw exactly one circle dimensioned to Ø84 mm centered on the Z axis. The finished sketch must yield two selectable profiles. Finish the sketch without extruding it.
+
+### Stage 11 of 24
+
+Continuing from the previous stage, using the Ø70 mm circle sketch, extrude its single profile by 3 mm in the global positive-Z direction, so the hub spans Z = 49 to Z = 52. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 12 of 24
+
+Continuing from the previous stage, using the body, create a sketch on the top disk face at Z = 49. Draw exactly one circle dimensioned to Ø70 mm centered on the Z axis. Finish the sketch without extruding it.
+
+### Stage 13 of 24
+
+Continuing from the previous stage, using the Ø70 mm circle sketch, extrude its single profile by 3 mm in the global positive-Z direction, so the hub spans Z = 49 to Z = 52. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 14 of 24
+
+Continuing from the previous stage, using the body, create a sketch on the top disk face at Z = 49. Draw exactly one circle dimensioned to Ø70 mm centered on the Z axis. Finish the sketch without extruding it.
+
+### Stage 15 of 24
+
+Continuing from the previous stage, using the bolt-boss sketch, select the annular region between the Ø3 mm and Ø4.5 mm circles — the radial line splits it into two half-ring profiles, so select both — and extrude it 1 mm in the global positive-Z direction, to Z = 50. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 16 of 24
+
+Continuing from the previous stage, using the single bolt-boss detail, create a Circular Pattern of that extrusion feature around the global Z axis. Use Full distribution over 360°, quantity 16, and Identical compute type, placing bosses every 22.5° on the Ø77 bolt circle (radius 38.5). Pattern the feature, not sketch geometry or faces, and add no other feature.
+
+### Stage 17 of 24
+
+Continuing from the previous stage, using the body, create a sketch on the bottom disk face at Z = 0. Draw a center rectangle with diagonals, centered on the origin, dimensioned 24 mm along X and 40 mm along Y (corners at X = ±12, Y = ±20). Finish the sketch without extruding it.
+
+### Stage 18 of 24
+
+Continuing from the previous stage, using the 24 × 40 mm rectangle sketch, extrude its single profile by 42 mm in the global negative-Z direction, so the tang spans Z = 0 to Z = −42. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 19 of 24
+
+Continuing from the previous stage, using the body, create a sketch on the tang side face at X = −12. Draw exactly one circle dimensioned to Ø40 mm centered at global (−12, 0, −42), the tang end. Finish the sketch without extruding it.
+
+### Stage 20 of 24
+
+Continuing from the previous stage, using the Ø40 mm circle sketch, extrude its single profile −24 mm through the tang (from X = −12 to X = +12) with 0° taper and Join, forming the rounded Ø40 knob at the tang end. Add no other feature.
+
+### Stage 21 of 24
+
+Continuing from the previous stage, using the body, create a sketch on the tang side face at X = −12. Draw exactly one circle dimensioned to Ø20 mm, placed near the knob center — its final center is at global (−12, 0, −40), 2 mm above the Ø40 knob center. Finish the sketch without extruding it.
+
+### Stage 22 of 24
+
+Continuing from the previous stage, using the Ø20 mm circle sketch, extrude its single profile by 10 mm in the global negative-X direction, so the pin spans X = −12 to X = −22. Use a one-sided extrusion, 0° taper, and Join. Add no other feature.
+
+### Stage 23 of 24
+
+Continuing from the previous stage, using the body, create a sketch on the hub face at Z = 52. Draw exactly one circle at the face center (0, 0, 52) and type its diameter as 20 mm. Finish the sketch without extruding it.
+
+### Stage 24 of 24
+
+Continuing from the previous stage, using the Ø20 mm circle sketch, extrude its single profile by 10 mm in the global positive-Z direction, so the stud spans Z = 52 to Z = 62. Use a one-sided extrusion, 0° taper, and Join. This completes the Jaw_5 geometry: 24 timeline features, one solid body, bounding box X ±42, Y ±37, Z −62..+62. Add no other feature.
+
+End state across all stages: exactly 12 new sketches, 11 new extrusion or revolve features, 1 circular pattern feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch01_hub_stack/task.md

@@ -1,3 +1,25 @@
 # Build the boss, shaft, and bolt-ring stack
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 3 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 3
+
+Starting from the supplied body after its 35 mm, −15° tapered extension, create a fully constrained sketch on the exposed terminal face. Draw exactly one Ø69 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circle 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 2 of 3
+
+On the Ø69 mm boss from the previous stage, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circular profile 30 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 3 of 3
+
+On the exposed Ø62 mm terminal face from the previous stage, create a fully constrained sketch on that face. On the positive horizontal sketch axis, place the center of a Ø5 mm circle exactly 27 mm from the shaft center. Offset that circle inward by 1 mm using a −1 mm sketch offset, producing a concentric Ø3 mm circle. Finish the sketch, then select only the annulus between Ø3 mm and Ø5 mm and extrude it 1 mm outward in the positive X direction with a one-sided 0° Join extrusion. Do not extrude the inner disk and do not create a pattern. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+End state across all stages: exactly 3 new sketches, 3 new extrusion or cut features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch01_hub_stack_free/task.md

@@ -1,3 +1,25 @@
 # Build the boss, shaft, and bolt-ring stack
 
-Hard · Fusion API allowed · Match [`answer.f3d`](./answer.f3d).
+Complete the CAD task below in Autodesk Fusion. You may build the geometry with the normal Fusion user interface, or by writing Fusion 360 Python API (adsk) code and executing it in Fusion's Text Commands palette (open it from the View menu if hidden, and make sure the input mode toggle at the bottom right of the palette is set to Py, not Txt), or any combination of both. Work in the root component and use millimetres. Do not use a terminal outside Fusion and do not open or import any external CAD file.
+
+This is a multi-stage build with 3 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 3
+
+Starting from the supplied body after its 35 mm, −15° tapered extension, create a fully constrained sketch on the exposed terminal face. Draw exactly one Ø69 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circle 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 2 of 3
+
+On the Ø69 mm boss from the previous stage, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circular profile 30 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 3 of 3
+
+On the exposed Ø62 mm terminal face from the previous stage, create a fully constrained sketch on that face. On the positive horizontal sketch axis, place the center of a Ø5 mm circle exactly 27 mm from the shaft center. Offset that circle inward by 1 mm using a −1 mm sketch offset, producing a concentric Ø3 mm circle. Finish the sketch, then select only the annulus between Ø3 mm and Ø5 mm and extrude it 1 mm outward in the positive X direction with a one-sided 0° Join extrusion. Do not extrude the inner disk and do not create a pattern. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+End state across all stages: exactly 3 new sketches, 3 new extrusion or cut features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch01s_hub_stack_spec/task.md

@@ -1,3 +1,27 @@
 # Build the three-feature hub stack
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+## Required result
+
+Continue in the document that is already open (work in a different document
+scores zero). Starting from the supplied tapered housing, add exactly three
+features to the end of the part, in order. Each feature is one fully
+constrained sketch on the then-current exposed terminal face plus one
+one-sided extrusion in the positive X direction with 0° taper and Join:
+
+1. Boss: Ø69 mm circular boss, 10 mm long, concentric with the main X
+   axis.
+2. Shaft: Ø62 mm circular shaft, 30 mm long, concentric with the main X
+   axis.
+3. Bolt detail: an annular pad 1 mm high on the shaft's end face — the
+   ring between concentric Ø5 mm and Ø3 mm circles whose common
+   center lies on the positive horizontal sketch axis, 27 mm from the shaft
+   center. Extrude only the annulus (not the inner disk); no pattern.
+
+End state: exactly three new sketches, three new extrusion features, and one
+solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch01s_hub_stack_spec_free/task.md

@@ -1,3 +1,27 @@
 # Build the three-feature hub stack
 
-Hard · Fusion API allowed · Match [`answer.f3d`](./answer.f3d).
+Complete the CAD task below in Autodesk Fusion. You may build the geometry with the normal Fusion user interface, or by writing Fusion 360 Python API (adsk) code and executing it in Fusion's Text Commands palette (open it from the View menu if hidden, and make sure the input mode toggle at the bottom right of the palette is set to Py, not Txt), or any combination of both. Work in the root component and use millimetres. Do not use a terminal outside Fusion and do not open or import any external CAD file.
+
+## Required result
+
+Continue in the document that is already open (work in a different document
+scores zero). Starting from the supplied tapered housing, add exactly three
+features to the end of the part, in order. Each feature is one fully
+constrained sketch on the then-current exposed terminal face plus one
+one-sided extrusion in the positive X direction with 0° taper and Join:
+
+1. Boss: Ø69 mm circular boss, 10 mm long, concentric with the main X
+   axis.
+2. Shaft: Ø62 mm circular shaft, 30 mm long, concentric with the main X
+   axis.
+3. Bolt detail: an annular pad 1 mm high on the shaft's end face — the
+   ring between concentric Ø5 mm and Ø3 mm circles whose common
+   center lies on the positive horizontal sketch axis, 27 mm from the shaft
+   center. Extrude only the annulus (not the inner disk); no pattern.
+
+End state: exactly three new sketches, three new extrusion features, and one
+solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch02_flange_stack/task.md

@@ -1,3 +1,25 @@
 # Build the double end flange with raised inset
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 3 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 3
+
+Starting from the supplied 100 mm keyed shaft, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both face regions inside the Ø62 mm boundary—the keyed central region and its surrounding region—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be one complete Ø62 mm circular flange, one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 2 of 3
+
+On the Ø62 mm flange from the previous stage, create a new fully constrained sketch on the flange's exposed terminal face. Offset the Ø62 mm circular perimeter inward by 1 mm using a −1 mm sketch offset, producing exactly one centered Ø60 mm profile. Finish the sketch, then extrude the central Ø60 mm disk—not the surrounding annulus—1 mm outward in the positive X direction with a one-sided 0° Join extrusion. The result must be a solid raised Ø60 mm disk with no enclosed cavity, exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 3 of 3
+
+On the raised Ø60 mm end face from the previous stage, create a fully constrained sketch on that face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both regions inside the Ø62 mm boundary—the central Ø60 mm face and the surrounding Ø60-to-Ø62 mm annulus—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be a complete Ø62 mm circular end flange, exactly one new sketch, one new extrusion feature, and one solid body.
+
+End state across all stages: exactly 3 new sketches, 3 new extrusion or cut features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch02_flange_stack_free/task.md

@@ -1,3 +1,25 @@
 # Build the double end flange with raised inset
 
-Hard · Fusion API allowed · Match [`answer.f3d`](./answer.f3d).
+Complete the CAD task below in Autodesk Fusion. You may build the geometry with the normal Fusion user interface, or by writing Fusion 360 Python API (adsk) code and executing it in Fusion's Text Commands palette (open it from the View menu if hidden, and make sure the input mode toggle at the bottom right of the palette is set to Py, not Txt), or any combination of both. Work in the root component and use millimetres. Do not use a terminal outside Fusion and do not open or import any external CAD file.
+
+This is a multi-stage build with 3 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 3
+
+Starting from the supplied 100 mm keyed shaft, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both face regions inside the Ø62 mm boundary—the keyed central region and its surrounding region—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be one complete Ø62 mm circular flange, one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 2 of 3
+
+On the Ø62 mm flange from the previous stage, create a new fully constrained sketch on the flange's exposed terminal face. Offset the Ø62 mm circular perimeter inward by 1 mm using a −1 mm sketch offset, producing exactly one centered Ø60 mm profile. Finish the sketch, then extrude the central Ø60 mm disk—not the surrounding annulus—1 mm outward in the positive X direction with a one-sided 0° Join extrusion. The result must be a solid raised Ø60 mm disk with no enclosed cavity, exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 3 of 3
+
+On the raised Ø60 mm end face from the previous stage, create a fully constrained sketch on that face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both regions inside the Ø62 mm boundary—the central Ø60 mm face and the surrounding Ø60-to-Ø62 mm annulus—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be a complete Ø62 mm circular end flange, exactly one new sketch, one new extrusion feature, and one solid body.
+
+End state across all stages: exactly 3 new sketches, 3 new extrusion or cut features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch03_side_assembly/task.md

@@ -1,3 +1,25 @@
 # Build the side-disk assembly on a new construction plane
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 3 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 3
+
+Create a construction plane coincident with the flat positive-Z side face of the original untapered housing—the plane at global Z = 37.5 mm that contains the housing's two long parallel longitudinal edges. Any construction-plane method that produces a plane exactly coincident with that face is acceptable. Add nothing else in this stage: no sketch and no solid feature.
+
+### Stage 2 of 3
+
+On the construction plane you just created, make a fully constrained sketch. Draw exactly one Ø85 mm circle centered at the midpoint of the lower longitudinal edge of the original 100 mm housing section: global X = 50 mm, Y = −45 mm, Z = 37.5 mm. Finish the sketch, then extrude the circular profile symmetrically about that plane by 10.5 mm on each side, for 21 mm total thickness, with 0° taper and Join. The disk must span global Z = 27 mm to Z = 48 mm and remain part of the single body. This stage adds exactly one new sketch and one new extrusion feature.
+
+### Stage 3 of 3
+
+On the Ø85 mm side disk from the previous stage, create a fully constrained sketch on its negative-Z planar face at global Z = 27 mm. Use the existing straight lower housing edge to close the top of one support profile. Place two vertical sketch lines at global X = 30 mm and X = 70 mm, start both on the housing edge at Y = −45 mm, and extend each 30 mm toward negative Y to Y = −75 mm. Connect their lower endpoints with a minor R30 mm arc bulging toward negative Y. Finish the sketch, then extrude that one closed profile 35 mm from Z = 27 mm toward negative Z, ending at Z = −8 mm, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+End state across all stages: exactly 2 new sketches, 2 new extrusion or cut features, one construction plane, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch03_side_assembly_free/task.md

@@ -1,3 +1,25 @@
 # Build the side-disk assembly on a new construction plane
 
-Hard · Fusion API allowed · Match [`answer.f3d`](./answer.f3d).
+Complete the CAD task below in Autodesk Fusion. You may build the geometry with the normal Fusion user interface, or by writing Fusion 360 Python API (adsk) code and executing it in Fusion's Text Commands palette (open it from the View menu if hidden, and make sure the input mode toggle at the bottom right of the palette is set to Py, not Txt), or any combination of both. Work in the root component and use millimetres. Do not use a terminal outside Fusion and do not open or import any external CAD file.
+
+This is a multi-stage build with 3 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 3
+
+Create a construction plane coincident with the flat positive-Z side face of the original untapered housing—the plane at global Z = 37.5 mm that contains the housing's two long parallel longitudinal edges. Any construction-plane method that produces a plane exactly coincident with that face is acceptable. Add nothing else in this stage: no sketch and no solid feature.
+
+### Stage 2 of 3
+
+On the construction plane you just created, make a fully constrained sketch. Draw exactly one Ø85 mm circle centered at the midpoint of the lower longitudinal edge of the original 100 mm housing section: global X = 50 mm, Y = −45 mm, Z = 37.5 mm. Finish the sketch, then extrude the circular profile symmetrically about that plane by 10.5 mm on each side, for 21 mm total thickness, with 0° taper and Join. The disk must span global Z = 27 mm to Z = 48 mm and remain part of the single body. This stage adds exactly one new sketch and one new extrusion feature.
+
+### Stage 3 of 3
+
+On the Ø85 mm side disk from the previous stage, create a fully constrained sketch on its negative-Z planar face at global Z = 27 mm. Use the existing straight lower housing edge to close the top of one support profile. Place two vertical sketch lines at global X = 30 mm and X = 70 mm, start both on the housing edge at Y = −45 mm, and extend each 30 mm toward negative Y to Y = −75 mm. Connect their lower endpoints with a minor R30 mm arc bulging toward negative Y. Finish the sketch, then extrude that one closed profile 35 mm from Z = 27 mm toward negative Z, ending at Z = −8 mm, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+End state across all stages: exactly 2 new sketches, 2 new extrusion or cut features, one construction plane, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch04_base_front/task.md

@@ -1,3 +1,33 @@
 # Build the housing front end from a blank design
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 5 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 5
+
+In the empty millimetre design that is already open (do not create a new document), create a fully constrained sketch on the YZ (Right) origin plane. Use global coordinates so the horizontal sketch edges lie at Y = +45 mm and Y = −45 mm and extend from Z = −37.5 mm to Z = +37.5 mm. Split each horizontal edge at Z = 0 and keep an ordinary divider along Z = 0 between their midpoints, producing two adjacent closed regions. Connect the two Z = −37.5 mm endpoints with a minor R125 mm arc bulging toward negative Z, and mirror it on the Z = +37.5 mm side. Finish the sketch, then extrude both closed regions together 100 mm in the positive X direction with 0° taper and New Body. This stage produces exactly one fully constrained sketch and one extrusion feature, leaving a single solid body.
+
+### Stage 2 of 5
+
+Extend the housing with a tapered section: select the flat end face of the base extrusion at X = 100 mm and extrude that face directly—without creating any new sketch—35 mm further in the positive X direction with a −15° taper angle, one-sided, Join. The housing must now end at X = 135 mm with inward-sloping side walls. This stage adds exactly one new extrusion feature and no sketch, keeping a single solid body.
+
+### Stage 3 of 5
+
+On the tapered extension you just created, create a fully constrained sketch on the exposed terminal face. Draw exactly one Ø69 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circle 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 4 of 5
+
+On the Ø69 mm boss from the previous stage, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circular profile 30 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 5 of 5
+
+On the exposed Ø62 mm terminal face from the previous stage, create a fully constrained sketch on that face. On the positive horizontal sketch axis, place the center of a Ø5 mm circle exactly 27 mm from the shaft center. Offset that circle inward by 1 mm using a −1 mm sketch offset, producing a concentric Ø3 mm circle. Finish the sketch, then select only the annulus between Ø3 mm and Ø5 mm and extrude it 1 mm outward in the positive X direction with a one-sided 0° Join extrusion. Do not extrude the inner disk and do not create a pattern. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+End state across all stages: exactly 4 new sketches, 5 new extrusion or cut features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch04_base_front_free/task.md

@@ -1,3 +1,33 @@
 # Build the housing front end from a blank design
 
-Hard · Fusion API allowed · Match [`answer.f3d`](./answer.f3d).
+Complete the CAD task below in Autodesk Fusion. You may build the geometry with the normal Fusion user interface, or by writing Fusion 360 Python API (adsk) code and executing it in Fusion's Text Commands palette (open it from the View menu if hidden, and make sure the input mode toggle at the bottom right of the palette is set to Py, not Txt), or any combination of both. Work in the root component and use millimetres. Do not use a terminal outside Fusion and do not open or import any external CAD file.
+
+This is a multi-stage build with 5 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 5
+
+In the empty millimetre design that is already open (do not create a new document), create a fully constrained sketch on the YZ (Right) origin plane. Use global coordinates so the horizontal sketch edges lie at Y = +45 mm and Y = −45 mm and extend from Z = −37.5 mm to Z = +37.5 mm. Split each horizontal edge at Z = 0 and keep an ordinary divider along Z = 0 between their midpoints, producing two adjacent closed regions. Connect the two Z = −37.5 mm endpoints with a minor R125 mm arc bulging toward negative Z, and mirror it on the Z = +37.5 mm side. Finish the sketch, then extrude both closed regions together 100 mm in the positive X direction with 0° taper and New Body. This stage produces exactly one fully constrained sketch and one extrusion feature, leaving a single solid body.
+
+### Stage 2 of 5
+
+Extend the housing with a tapered section: select the flat end face of the base extrusion at X = 100 mm and extrude that face directly—without creating any new sketch—35 mm further in the positive X direction with a −15° taper angle, one-sided, Join. The housing must now end at X = 135 mm with inward-sloping side walls. This stage adds exactly one new extrusion feature and no sketch, keeping a single solid body.
+
+### Stage 3 of 5
+
+On the tapered extension you just created, create a fully constrained sketch on the exposed terminal face. Draw exactly one Ø69 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circle 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 4 of 5
+
+On the Ø69 mm boss from the previous stage, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circular profile 30 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 5 of 5
+
+On the exposed Ø62 mm terminal face from the previous stage, create a fully constrained sketch on that face. On the positive horizontal sketch axis, place the center of a Ø5 mm circle exactly 27 mm from the shaft center. Offset that circle inward by 1 mm using a −1 mm sketch offset, producing a concentric Ø3 mm circle. Finish the sketch, then select only the annulus between Ø3 mm and Ø5 mm and extrude it 1 mm outward in the positive X direction with a one-sided 0° Join extrusion. Do not extrude the inner disk and do not create a pattern. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+End state across all stages: exactly 4 new sketches, 5 new extrusion or cut features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch05_pattern_key/task.md

@@ -1,3 +1,25 @@
 # Pattern the bolt detail and build the keyed shaft
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 3 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 3
+
+Starting from the supplied Ø62 mm terminal face, create a fully constrained sketch on that face. On the positive horizontal sketch axis, place the center of a Ø5 mm circle exactly 27 mm from the shaft center. Offset that circle inward by 1 mm using a −1 mm sketch offset, producing a concentric Ø3 mm circle. Finish the sketch, then select only the annulus between Ø3 mm and Ø5 mm and extrude it 1 mm outward in the positive X direction with a one-sided 0° Join extrusion. Do not extrude the inner disk and do not create a pattern in this stage—the circular pattern is the next stage. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 2 of 3
+
+Create a circular pattern of the raised annular bolt detail: use a feature circular pattern (pattern the extrusion feature itself, not sketch geometry or faces), select the 1 mm annular pad from the previous stage, set the pattern axis to the main shaft axis (the X axis), quantity 12, full 360° distribution with equal spacing. The result is twelve identical raised annular details arranged around the shaft's terminal face. This stage adds exactly one circular pattern feature and nothing else, keeping a single solid body.
+
+### Stage 3 of 3
+
+On the patterned terminal face from the previous stage, create one fully constrained, centered shaft-profile sketch. In global YZ coordinates, draw straight side segments at Z = −16 mm and Z = +16 mm, each extending from Y = −17 mm to Y = +17 mm. Connect the upper endpoints with a minor R22 mm arc bulging toward positive Y and the lower endpoints with a separate minor R22 mm arc bulging toward negative Y. Keep one closed profile with no center divider. Finish the sketch, then extrude that profile 100 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage ends with two distinct R22 curved shaft faces, adding exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+End state across all stages: exactly 2 new sketches, 2 new extrusion or cut features, one circular pattern feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch05_pattern_key_free/task.md

@@ -1,3 +1,25 @@
 # Pattern the bolt detail and build the keyed shaft
 
-Hard · Fusion API allowed · Match [`answer.f3d`](./answer.f3d).
+Complete the CAD task below in Autodesk Fusion. You may build the geometry with the normal Fusion user interface, or by writing Fusion 360 Python API (adsk) code and executing it in Fusion's Text Commands palette (open it from the View menu if hidden, and make sure the input mode toggle at the bottom right of the palette is set to Py, not Txt), or any combination of both. Work in the root component and use millimetres. Do not use a terminal outside Fusion and do not open or import any external CAD file.
+
+This is a multi-stage build with 3 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 3
+
+Starting from the supplied Ø62 mm terminal face, create a fully constrained sketch on that face. On the positive horizontal sketch axis, place the center of a Ø5 mm circle exactly 27 mm from the shaft center. Offset that circle inward by 1 mm using a −1 mm sketch offset, producing a concentric Ø3 mm circle. Finish the sketch, then select only the annulus between Ø3 mm and Ø5 mm and extrude it 1 mm outward in the positive X direction with a one-sided 0° Join extrusion. Do not extrude the inner disk and do not create a pattern in this stage—the circular pattern is the next stage. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 2 of 3
+
+Create a circular pattern of the raised annular bolt detail: use a feature circular pattern (pattern the extrusion feature itself, not sketch geometry or faces), select the 1 mm annular pad from the previous stage, set the pattern axis to the main shaft axis (the X axis), quantity 12, full 360° distribution with equal spacing. The result is twelve identical raised annular details arranged around the shaft's terminal face. This stage adds exactly one circular pattern feature and nothing else, keeping a single solid body.
+
+### Stage 3 of 3
+
+On the patterned terminal face from the previous stage, create one fully constrained, centered shaft-profile sketch. In global YZ coordinates, draw straight side segments at Z = −16 mm and Z = +16 mm, each extending from Y = −17 mm to Y = +17 mm. Connect the upper endpoints with a minor R22 mm arc bulging toward positive Y and the lower endpoints with a separate minor R22 mm arc bulging toward negative Y. Keep one closed profile with no center divider. Finish the sketch, then extrude that profile 100 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage ends with two distinct R22 curved shaft faces, adding exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+End state across all stages: exactly 2 new sketches, 2 new extrusion or cut features, one circular pattern feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch06_tail_gusset/task.md

@@ -1,3 +1,29 @@
 # Build the gusset, trim it, and cut both holes
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 4 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 4
+
+Starting from the supplied joined lower support, create a fully constrained sketch on the support's axial end face at global X = 70 mm, perpendicular to the main X axis. Use the existing straight support edge between the exposed upper housing/support corner and the exposed lower support corner as the closing chord; do not assign an invented chord length. From the upper corner, draw a 25 mm top segment in the support-face horizontal direction, then connect its far endpoint to the existing lower corner with a minor R55 mm arc bulging outward. Finish the resulting closed curved gusset profile, then extrude that profile 40 mm in the negative X direction using a one-sided −40 mm distance, 0° taper, and Join. Stop before the trimming cut (that is the next stage), with exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 2 of 4
+
+Trim the lower support region outside the curved gusset: reuse the gusset sketch from the previous stage—select the remaining closed region between the gusset arc and the support outline (the lower region you did not extrude)—and extrude-cut it 40 mm in the negative X direction, one-sided −40 mm distance, 0° taper, operation Cut. Do not create a new sketch. The cut removes the support material outside the curved gusset so the support's end matches the gusset profile. This stage adds exactly one new cut feature and no sketch, keeping a single solid body.
+
+### Stage 3 of 4
+
+With the side disk and trimmed support complete, create a fully constrained sketch on the positive-Z outer planar face of the Ø85 mm side disk at global Z = 48 mm. Draw exactly one Ø30 mm circle concentric with the disk at global X = 50 mm and Y = −45 mm. Finish the sketch, then extrude-cut that profile 20 mm in the negative Z direction using a one-sided −20 mm distance and 0° taper. Do not use Through All and do not create the axial end-flange hole yet—that is the final stage. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+### Stage 4 of 4
+
+With the side-disk cut complete, create a fully constrained sketch on the exposed axial end face of the final Ø62 mm flange at global X = 296 mm. Draw exactly one Ø30 mm circle concentric with the main X axis and coincident with the end-face center. Finish the sketch, then extrude-cut that profile 20 mm in the negative X direction using a one-sided −20 mm distance and 0° taper. This must create the separate axial end-flange hole; do not add a second sketch or cut on the side disk. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+End state across all stages: exactly 3 new sketches, 4 new extrusion or cut features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch06_tail_gusset_free/task.md

@@ -1,3 +1,29 @@
 # Build the gusset, trim it, and cut both holes
 
-Hard · Fusion API allowed · Match [`answer.f3d`](./answer.f3d).
+Complete the CAD task below in Autodesk Fusion. You may build the geometry with the normal Fusion user interface, or by writing Fusion 360 Python API (adsk) code and executing it in Fusion's Text Commands palette (open it from the View menu if hidden, and make sure the input mode toggle at the bottom right of the palette is set to Py, not Txt), or any combination of both. Work in the root component and use millimetres. Do not use a terminal outside Fusion and do not open or import any external CAD file.
+
+This is a multi-stage build with 4 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 4
+
+Starting from the supplied joined lower support, create a fully constrained sketch on the support's axial end face at global X = 70 mm, perpendicular to the main X axis. Use the existing straight support edge between the exposed upper housing/support corner and the exposed lower support corner as the closing chord; do not assign an invented chord length. From the upper corner, draw a 25 mm top segment in the support-face horizontal direction, then connect its far endpoint to the existing lower corner with a minor R55 mm arc bulging outward. Finish the resulting closed curved gusset profile, then extrude that profile 40 mm in the negative X direction using a one-sided −40 mm distance, 0° taper, and Join. Stop before the trimming cut (that is the next stage), with exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 2 of 4
+
+Trim the lower support region outside the curved gusset: reuse the gusset sketch from the previous stage—select the remaining closed region between the gusset arc and the support outline (the lower region you did not extrude)—and extrude-cut it 40 mm in the negative X direction, one-sided −40 mm distance, 0° taper, operation Cut. Do not create a new sketch. The cut removes the support material outside the curved gusset so the support's end matches the gusset profile. This stage adds exactly one new cut feature and no sketch, keeping a single solid body.
+
+### Stage 3 of 4
+
+With the side disk and trimmed support complete, create a fully constrained sketch on the positive-Z outer planar face of the Ø85 mm side disk at global Z = 48 mm. Draw exactly one Ø30 mm circle concentric with the disk at global X = 50 mm and Y = −45 mm. Finish the sketch, then extrude-cut that profile 20 mm in the negative Z direction using a one-sided −20 mm distance and 0° taper. Do not use Through All and do not create the axial end-flange hole yet—that is the final stage. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+### Stage 4 of 4
+
+With the side-disk cut complete, create a fully constrained sketch on the exposed axial end face of the final Ø62 mm flange at global X = 296 mm. Draw exactly one Ø30 mm circle concentric with the main X axis and coincident with the end-face center. Finish the sketch, then extrude-cut that profile 20 mm in the negative X direction using a one-sided −20 mm distance and 0° taper. This must create the separate axial end-flange hole; do not add a second sketch or cut on the side disk. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+End state across all stages: exactly 3 new sketches, 4 new extrusion or cut features, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch07_mid_span/task.md

@@ -1,3 +1,33 @@
 # Build the mid section from shaft to first flange
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 5 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 5
+
+Starting from the supplied Ø69 mm boss, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circular profile 30 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 2 of 5
+
+On the exposed Ø62 mm terminal face from the previous stage, create a fully constrained sketch on that face. On the positive horizontal sketch axis, place the center of a Ø5 mm circle exactly 27 mm from the shaft center. Offset that circle inward by 1 mm using a −1 mm sketch offset, producing a concentric Ø3 mm circle. Finish the sketch, then select only the annulus between Ø3 mm and Ø5 mm and extrude it 1 mm outward in the positive X direction with a one-sided 0° Join extrusion. Do not extrude the inner disk and do not create a pattern in this stage—the circular pattern is the next stage. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 3 of 5
+
+Create a circular pattern of the raised annular bolt detail: use a feature circular pattern (pattern the extrusion feature itself, not sketch geometry or faces), select the 1 mm annular pad from the previous stage, set the pattern axis to the main shaft axis (the X axis), quantity 12, full 360° distribution with equal spacing. The result is twelve identical raised annular details arranged around the shaft's terminal face. This stage adds exactly one circular pattern feature and nothing else, keeping a single solid body.
+
+### Stage 4 of 5
+
+On the patterned terminal face from the previous stage, create one fully constrained, centered shaft-profile sketch. In global YZ coordinates, draw straight side segments at Z = −16 mm and Z = +16 mm, each extending from Y = −17 mm to Y = +17 mm. Connect the upper endpoints with a minor R22 mm arc bulging toward positive Y and the lower endpoints with a separate minor R22 mm arc bulging toward negative Y. Keep one closed profile with no center divider. Finish the sketch, then extrude that profile 100 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage ends with two distinct R22 curved shaft faces, adding exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 5 of 5
+
+On the 100 mm keyed shaft from the previous stage, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both face regions inside the Ø62 mm boundary—the keyed central region and its surrounding region—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be one complete Ø62 mm circular flange, one new sketch, one new extrusion feature, and one solid body.
+
+End state across all stages: exactly 4 new sketches, 4 new extrusion or cut features, one circular pattern feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch07_mid_span_free/task.md

@@ -1,3 +1,33 @@
 # Build the mid section from shaft to first flange
 
-Hard · Fusion API allowed · Match [`answer.f3d`](./answer.f3d).
+Complete the CAD task below in Autodesk Fusion. You may build the geometry with the normal Fusion user interface, or by writing Fusion 360 Python API (adsk) code and executing it in Fusion's Text Commands palette (open it from the View menu if hidden, and make sure the input mode toggle at the bottom right of the palette is set to Py, not Txt), or any combination of both. Work in the root component and use millimetres. Do not use a terminal outside Fusion and do not open or import any external CAD file.
+
+This is a multi-stage build with 5 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 5
+
+Starting from the supplied Ø69 mm boss, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circular profile 30 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 2 of 5
+
+On the exposed Ø62 mm terminal face from the previous stage, create a fully constrained sketch on that face. On the positive horizontal sketch axis, place the center of a Ø5 mm circle exactly 27 mm from the shaft center. Offset that circle inward by 1 mm using a −1 mm sketch offset, producing a concentric Ø3 mm circle. Finish the sketch, then select only the annulus between Ø3 mm and Ø5 mm and extrude it 1 mm outward in the positive X direction with a one-sided 0° Join extrusion. Do not extrude the inner disk and do not create a pattern in this stage—the circular pattern is the next stage. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 3 of 5
+
+Create a circular pattern of the raised annular bolt detail: use a feature circular pattern (pattern the extrusion feature itself, not sketch geometry or faces), select the 1 mm annular pad from the previous stage, set the pattern axis to the main shaft axis (the X axis), quantity 12, full 360° distribution with equal spacing. The result is twelve identical raised annular details arranged around the shaft's terminal face. This stage adds exactly one circular pattern feature and nothing else, keeping a single solid body.
+
+### Stage 4 of 5
+
+On the patterned terminal face from the previous stage, create one fully constrained, centered shaft-profile sketch. In global YZ coordinates, draw straight side segments at Z = −16 mm and Z = +16 mm, each extending from Y = −17 mm to Y = +17 mm. Connect the upper endpoints with a minor R22 mm arc bulging toward positive Y and the lower endpoints with a separate minor R22 mm arc bulging toward negative Y. Keep one closed profile with no center divider. Finish the sketch, then extrude that profile 100 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage ends with two distinct R22 curved shaft faces, adding exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 5 of 5
+
+On the 100 mm keyed shaft from the previous stage, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both face regions inside the Ø62 mm boundary—the keyed central region and its surrounding region—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be one complete Ø62 mm circular flange, one new sketch, one new extrusion feature, and one solid body.
+
+End state across all stages: exactly 4 new sketches, 4 new extrusion or cut features, one circular pattern feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch08_back_half/task.md

@@ -1,3 +1,49 @@
 # Complete the back half of the jaw housing
 
-Expert · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 9 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 9
+
+Starting from the supplied Ø62 mm flange whose earlier sketch already contains the corrected inward Ø60 mm offset, create a new fully constrained sketch on the flange's exposed terminal face. Offset the Ø62 mm circular perimeter inward by 1 mm using a −1 mm sketch offset, producing exactly one centered Ø60 mm profile. Finish the sketch, then extrude the central Ø60 mm disk—not the surrounding annulus—1 mm outward in the positive X direction with a one-sided 0° Join extrusion. The result must be a solid raised Ø60 mm disk with no enclosed cavity, exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 2 of 9
+
+On the raised Ø60 mm end face from the previous stage, create a fully constrained sketch on that face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both regions inside the Ø62 mm boundary—the central Ø60 mm face and the surrounding Ø60-to-Ø62 mm annulus—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be a complete Ø62 mm circular end flange, exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 3 of 9
+
+Create a construction plane coincident with the flat positive-Z side face of the original untapered housing—the plane at global Z = 37.5 mm that contains the housing's two long parallel longitudinal edges. Any construction-plane method that produces a plane exactly coincident with that face is acceptable. Add nothing else in this stage: no sketch and no solid feature.
+
+### Stage 4 of 9
+
+On the construction plane you just created, make a fully constrained sketch. Draw exactly one Ø85 mm circle centered at the midpoint of the lower longitudinal edge of the original 100 mm housing section: global X = 50 mm, Y = −45 mm, Z = 37.5 mm. Finish the sketch, then extrude the circular profile symmetrically about that plane by 10.5 mm on each side, for 21 mm total thickness, with 0° taper and Join. The disk must span global Z = 27 mm to Z = 48 mm and remain part of the single body. This stage adds exactly one new sketch and one new extrusion feature.
+
+### Stage 5 of 9
+
+On the Ø85 mm side disk from the previous stage, create a fully constrained sketch on its negative-Z planar face at global Z = 27 mm. Use the existing straight lower housing edge to close the top of one support profile. Place two vertical sketch lines at global X = 30 mm and X = 70 mm, start both on the housing edge at Y = −45 mm, and extend each 30 mm toward negative Y to Y = −75 mm. Connect their lower endpoints with a minor R30 mm arc bulging toward negative Y. Finish the sketch, then extrude that one closed profile 35 mm from Z = 27 mm toward negative Z, ending at Z = −8 mm, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 6 of 9
+
+On the joined lower support from the previous stage, create a fully constrained sketch on the support's axial end face at global X = 70 mm, perpendicular to the main X axis. Use the existing straight support edge between the exposed upper housing/support corner and the exposed lower support corner as the closing chord; do not assign an invented chord length. From the upper corner, draw a 25 mm top segment in the support-face horizontal direction, then connect its far endpoint to the existing lower corner with a minor R55 mm arc bulging outward. Finish the resulting closed curved gusset profile, then extrude that profile 40 mm in the negative X direction using a one-sided −40 mm distance, 0° taper, and Join. Stop before the trimming cut (that is the next stage), with exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 7 of 9
+
+Trim the lower support region outside the curved gusset: reuse the gusset sketch from the previous stage—select the remaining closed region between the gusset arc and the support outline (the lower region you did not extrude)—and extrude-cut it 40 mm in the negative X direction, one-sided −40 mm distance, 0° taper, operation Cut. Do not create a new sketch. The cut removes the support material outside the curved gusset so the support's end matches the gusset profile. This stage adds exactly one new cut feature and no sketch, keeping a single solid body.
+
+### Stage 8 of 9
+
+With the side disk and trimmed support complete, create a fully constrained sketch on the positive-Z outer planar face of the Ø85 mm side disk at global Z = 48 mm. Draw exactly one Ø30 mm circle concentric with the disk at global X = 50 mm and Y = −45 mm. Finish the sketch, then extrude-cut that profile 20 mm in the negative Z direction using a one-sided −20 mm distance and 0° taper. Do not use Through All and do not create the axial end-flange hole yet—that is the final stage. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+### Stage 9 of 9
+
+With the side-disk cut complete, create a fully constrained sketch on the exposed axial end face of the final Ø62 mm flange at global X = 296 mm. Draw exactly one Ø30 mm circle concentric with the main X axis and coincident with the end-face center. Finish the sketch, then extrude-cut that profile 20 mm in the negative X direction using a one-sided −20 mm distance and 0° taper. This must create the separate axial end-flange hole; do not add a second sketch or cut on the side disk. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+End state across all stages: exactly 7 new sketches, 8 new extrusion or cut features, one construction plane, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch08_back_half_free/task.md

@@ -1,3 +1,49 @@
 # Complete the back half of the jaw housing
 
-Expert · Fusion API allowed · Match [`answer.f3d`](./answer.f3d).
+Complete the CAD task below in Autodesk Fusion. You may build the geometry with the normal Fusion user interface, or by writing Fusion 360 Python API (adsk) code and executing it in Fusion's Text Commands palette (open it from the View menu if hidden, and make sure the input mode toggle at the bottom right of the palette is set to Py, not Txt), or any combination of both. Work in the root component and use millimetres. Do not use a terminal outside Fusion and do not open or import any external CAD file.
+
+This is a multi-stage build with 9 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 9
+
+Starting from the supplied Ø62 mm flange whose earlier sketch already contains the corrected inward Ø60 mm offset, create a new fully constrained sketch on the flange's exposed terminal face. Offset the Ø62 mm circular perimeter inward by 1 mm using a −1 mm sketch offset, producing exactly one centered Ø60 mm profile. Finish the sketch, then extrude the central Ø60 mm disk—not the surrounding annulus—1 mm outward in the positive X direction with a one-sided 0° Join extrusion. The result must be a solid raised Ø60 mm disk with no enclosed cavity, exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 2 of 9
+
+On the raised Ø60 mm end face from the previous stage, create a fully constrained sketch on that face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both regions inside the Ø62 mm boundary—the central Ø60 mm face and the surrounding Ø60-to-Ø62 mm annulus—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be a complete Ø62 mm circular end flange, exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 3 of 9
+
+Create a construction plane coincident with the flat positive-Z side face of the original untapered housing—the plane at global Z = 37.5 mm that contains the housing's two long parallel longitudinal edges. Any construction-plane method that produces a plane exactly coincident with that face is acceptable. Add nothing else in this stage: no sketch and no solid feature.
+
+### Stage 4 of 9
+
+On the construction plane you just created, make a fully constrained sketch. Draw exactly one Ø85 mm circle centered at the midpoint of the lower longitudinal edge of the original 100 mm housing section: global X = 50 mm, Y = −45 mm, Z = 37.5 mm. Finish the sketch, then extrude the circular profile symmetrically about that plane by 10.5 mm on each side, for 21 mm total thickness, with 0° taper and Join. The disk must span global Z = 27 mm to Z = 48 mm and remain part of the single body. This stage adds exactly one new sketch and one new extrusion feature.
+
+### Stage 5 of 9
+
+On the Ø85 mm side disk from the previous stage, create a fully constrained sketch on its negative-Z planar face at global Z = 27 mm. Use the existing straight lower housing edge to close the top of one support profile. Place two vertical sketch lines at global X = 30 mm and X = 70 mm, start both on the housing edge at Y = −45 mm, and extend each 30 mm toward negative Y to Y = −75 mm. Connect their lower endpoints with a minor R30 mm arc bulging toward negative Y. Finish the sketch, then extrude that one closed profile 35 mm from Z = 27 mm toward negative Z, ending at Z = −8 mm, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 6 of 9
+
+On the joined lower support from the previous stage, create a fully constrained sketch on the support's axial end face at global X = 70 mm, perpendicular to the main X axis. Use the existing straight support edge between the exposed upper housing/support corner and the exposed lower support corner as the closing chord; do not assign an invented chord length. From the upper corner, draw a 25 mm top segment in the support-face horizontal direction, then connect its far endpoint to the existing lower corner with a minor R55 mm arc bulging outward. Finish the resulting closed curved gusset profile, then extrude that profile 40 mm in the negative X direction using a one-sided −40 mm distance, 0° taper, and Join. Stop before the trimming cut (that is the next stage), with exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 7 of 9
+
+Trim the lower support region outside the curved gusset: reuse the gusset sketch from the previous stage—select the remaining closed region between the gusset arc and the support outline (the lower region you did not extrude)—and extrude-cut it 40 mm in the negative X direction, one-sided −40 mm distance, 0° taper, operation Cut. Do not create a new sketch. The cut removes the support material outside the curved gusset so the support's end matches the gusset profile. This stage adds exactly one new cut feature and no sketch, keeping a single solid body.
+
+### Stage 8 of 9
+
+With the side disk and trimmed support complete, create a fully constrained sketch on the positive-Z outer planar face of the Ø85 mm side disk at global Z = 48 mm. Draw exactly one Ø30 mm circle concentric with the disk at global X = 50 mm and Y = −45 mm. Finish the sketch, then extrude-cut that profile 20 mm in the negative Z direction using a one-sided −20 mm distance and 0° taper. Do not use Through All and do not create the axial end-flange hole yet—that is the final stage. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+### Stage 9 of 9
+
+With the side-disk cut complete, create a fully constrained sketch on the exposed axial end face of the final Ø62 mm flange at global X = 296 mm. Draw exactly one Ø30 mm circle concentric with the main X axis and coincident with the end-face center. Finish the sketch, then extrude-cut that profile 20 mm in the negative X direction using a one-sided −20 mm distance and 0° taper. This must create the separate axial end-flange hole; do not add a second sketch or cut on the side disk. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+End state across all stages: exactly 7 new sketches, 8 new extrusion or cut features, one construction plane, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch09_full_build/task.md

@@ -1,3 +1,81 @@
 # Build the complete jaw housing from a blank design
 
-Expert · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+This is a multi-stage build with 17 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 17
+
+In the empty millimetre design that is already open (do not create a new document), create a fully constrained sketch on the YZ (Right) origin plane. Use global coordinates so the horizontal sketch edges lie at Y = +45 mm and Y = −45 mm and extend from Z = −37.5 mm to Z = +37.5 mm. Split each horizontal edge at Z = 0 and keep an ordinary divider along Z = 0 between their midpoints, producing two adjacent closed regions. Connect the two Z = −37.5 mm endpoints with a minor R125 mm arc bulging toward negative Z, and mirror it on the Z = +37.5 mm side. Finish the sketch, then extrude both closed regions together 100 mm in the positive X direction with 0° taper and New Body. This stage produces exactly one fully constrained sketch and one extrusion feature, leaving a single solid body.
+
+### Stage 2 of 17
+
+Extend the housing with a tapered section: select the flat end face of the base extrusion at X = 100 mm and extrude that face directly—without creating any new sketch—35 mm further in the positive X direction with a −15° taper angle, one-sided, Join. The housing must now end at X = 135 mm with inward-sloping side walls. This stage adds exactly one new extrusion feature and no sketch, keeping a single solid body.
+
+### Stage 3 of 17
+
+On the tapered extension you just created, create a fully constrained sketch on the exposed terminal face. Draw exactly one Ø69 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circle 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 4 of 17
+
+On the Ø69 mm boss from the previous stage, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circular profile 30 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 5 of 17
+
+On the exposed Ø62 mm terminal face from the previous stage, create a fully constrained sketch on that face. On the positive horizontal sketch axis, place the center of a Ø5 mm circle exactly 27 mm from the shaft center. Offset that circle inward by 1 mm using a −1 mm sketch offset, producing a concentric Ø3 mm circle. Finish the sketch, then select only the annulus between Ø3 mm and Ø5 mm and extrude it 1 mm outward in the positive X direction with a one-sided 0° Join extrusion. Do not extrude the inner disk and do not create a pattern in this stage—the circular pattern is the next stage. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 6 of 17
+
+Create a circular pattern of the raised annular bolt detail: use a feature circular pattern (pattern the extrusion feature itself, not sketch geometry or faces), select the 1 mm annular pad from the previous stage, set the pattern axis to the main shaft axis (the X axis), quantity 12, full 360° distribution with equal spacing. The result is twelve identical raised annular details arranged around the shaft's terminal face. This stage adds exactly one circular pattern feature and nothing else, keeping a single solid body.
+
+### Stage 7 of 17
+
+On the patterned terminal face from the previous stage, create one fully constrained, centered shaft-profile sketch. In global YZ coordinates, draw straight side segments at Z = −16 mm and Z = +16 mm, each extending from Y = −17 mm to Y = +17 mm. Connect the upper endpoints with a minor R22 mm arc bulging toward positive Y and the lower endpoints with a separate minor R22 mm arc bulging toward negative Y. Keep one closed profile with no center divider. Finish the sketch, then extrude that profile 100 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage ends with two distinct R22 curved shaft faces, adding exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 8 of 17
+
+On the 100 mm keyed shaft from the previous stage, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both face regions inside the Ø62 mm boundary—the keyed central region and its surrounding region—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be one complete Ø62 mm circular flange, one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 9 of 17
+
+On the Ø62 mm flange from the previous stage, create a new fully constrained sketch on the flange's exposed terminal face. Offset the Ø62 mm circular perimeter inward by 1 mm using a −1 mm sketch offset, producing exactly one centered Ø60 mm profile. Finish the sketch, then extrude the central Ø60 mm disk—not the surrounding annulus—1 mm outward in the positive X direction with a one-sided 0° Join extrusion. The result must be a solid raised Ø60 mm disk with no enclosed cavity, exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 10 of 17
+
+On the raised Ø60 mm end face from the previous stage, create a fully constrained sketch on that face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both regions inside the Ø62 mm boundary—the central Ø60 mm face and the surrounding Ø60-to-Ø62 mm annulus—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be a complete Ø62 mm circular end flange, exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 11 of 17
+
+Create a construction plane coincident with the flat positive-Z side face of the original untapered housing—the plane at global Z = 37.5 mm that contains the housing's two long parallel longitudinal edges. Any construction-plane method that produces a plane exactly coincident with that face is acceptable. Add nothing else in this stage: no sketch and no solid feature.
+
+### Stage 12 of 17
+
+On the construction plane you just created, make a fully constrained sketch. Draw exactly one Ø85 mm circle centered at the midpoint of the lower longitudinal edge of the original 100 mm housing section: global X = 50 mm, Y = −45 mm, Z = 37.5 mm. Finish the sketch, then extrude the circular profile symmetrically about that plane by 10.5 mm on each side, for 21 mm total thickness, with 0° taper and Join. The disk must span global Z = 27 mm to Z = 48 mm and remain part of the single body. This stage adds exactly one new sketch and one new extrusion feature.
+
+### Stage 13 of 17
+
+On the Ø85 mm side disk from the previous stage, create a fully constrained sketch on its negative-Z planar face at global Z = 27 mm. Use the existing straight lower housing edge to close the top of one support profile. Place two vertical sketch lines at global X = 30 mm and X = 70 mm, start both on the housing edge at Y = −45 mm, and extend each 30 mm toward negative Y to Y = −75 mm. Connect their lower endpoints with a minor R30 mm arc bulging toward negative Y. Finish the sketch, then extrude that one closed profile 35 mm from Z = 27 mm toward negative Z, ending at Z = −8 mm, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 14 of 17
+
+On the joined lower support from the previous stage, create a fully constrained sketch on the support's axial end face at global X = 70 mm, perpendicular to the main X axis. Use the existing straight support edge between the exposed upper housing/support corner and the exposed lower support corner as the closing chord; do not assign an invented chord length. From the upper corner, draw a 25 mm top segment in the support-face horizontal direction, then connect its far endpoint to the existing lower corner with a minor R55 mm arc bulging outward. Finish the resulting closed curved gusset profile, then extrude that profile 40 mm in the negative X direction using a one-sided −40 mm distance, 0° taper, and Join. Stop before the trimming cut (that is the next stage), with exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 15 of 17
+
+Trim the lower support region outside the curved gusset: reuse the gusset sketch from the previous stage—select the remaining closed region between the gusset arc and the support outline (the lower region you did not extrude)—and extrude-cut it 40 mm in the negative X direction, one-sided −40 mm distance, 0° taper, operation Cut. Do not create a new sketch. The cut removes the support material outside the curved gusset so the support's end matches the gusset profile. This stage adds exactly one new cut feature and no sketch, keeping a single solid body.
+
+### Stage 16 of 17
+
+With the side disk and trimmed support complete, create a fully constrained sketch on the positive-Z outer planar face of the Ø85 mm side disk at global Z = 48 mm. Draw exactly one Ø30 mm circle concentric with the disk at global X = 50 mm and Y = −45 mm. Finish the sketch, then extrude-cut that profile 20 mm in the negative Z direction using a one-sided −20 mm distance and 0° taper. Do not use Through All and do not create the axial end-flange hole yet—that is the final stage. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+### Stage 17 of 17
+
+With the side-disk cut complete, create a fully constrained sketch on the exposed axial end face of the final Ø62 mm flange at global X = 296 mm. Draw exactly one Ø30 mm circle concentric with the main X axis and coincident with the end-face center. Finish the sketch, then extrude-cut that profile 20 mm in the negative X direction using a one-sided −20 mm distance and 0° taper. This must create the separate axial end-flange hole; do not add a second sketch or cut on the side disk. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+End state across all stages: exactly 13 new sketches, 15 new extrusion or cut features, one circular pattern feature, one construction plane, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_ch09_full_build_free/task.md

@@ -1,3 +1,81 @@
 # Build the complete jaw housing from a blank design
 
-Expert · Fusion API allowed · Match [`answer.f3d`](./answer.f3d).
+Complete the CAD task below in Autodesk Fusion. You may build the geometry with the normal Fusion user interface, or by writing Fusion 360 Python API (adsk) code and executing it in Fusion's Text Commands palette (open it from the View menu if hidden, and make sure the input mode toggle at the bottom right of the palette is set to Py, not Txt), or any combination of both. Work in the root component and use millimetres. Do not use a terminal outside Fusion and do not open or import any external CAD file.
+
+This is a multi-stage build with 17 stages completed in one episode. Work strictly in the document that is already open: do not create a new document and do not open or import any file—work done in a different document scores zero. Complete the stages in order; each stage builds on the result of the previous one. Do not add solid features beyond those specified.
+
+## Required result
+
+### Stage 1 of 17
+
+In the empty millimetre design that is already open (do not create a new document), create a fully constrained sketch on the YZ (Right) origin plane. Use global coordinates so the horizontal sketch edges lie at Y = +45 mm and Y = −45 mm and extend from Z = −37.5 mm to Z = +37.5 mm. Split each horizontal edge at Z = 0 and keep an ordinary divider along Z = 0 between their midpoints, producing two adjacent closed regions. Connect the two Z = −37.5 mm endpoints with a minor R125 mm arc bulging toward negative Z, and mirror it on the Z = +37.5 mm side. Finish the sketch, then extrude both closed regions together 100 mm in the positive X direction with 0° taper and New Body. This stage produces exactly one fully constrained sketch and one extrusion feature, leaving a single solid body.
+
+### Stage 2 of 17
+
+Extend the housing with a tapered section: select the flat end face of the base extrusion at X = 100 mm and extrude that face directly—without creating any new sketch—35 mm further in the positive X direction with a −15° taper angle, one-sided, Join. The housing must now end at X = 135 mm with inward-sloping side walls. This stage adds exactly one new extrusion feature and no sketch, keeping a single solid body.
+
+### Stage 3 of 17
+
+On the tapered extension you just created, create a fully constrained sketch on the exposed terminal face. Draw exactly one Ø69 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circle 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 4 of 17
+
+On the Ø69 mm boss from the previous stage, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch, then extrude the circular profile 30 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 5 of 17
+
+On the exposed Ø62 mm terminal face from the previous stage, create a fully constrained sketch on that face. On the positive horizontal sketch axis, place the center of a Ø5 mm circle exactly 27 mm from the shaft center. Offset that circle inward by 1 mm using a −1 mm sketch offset, producing a concentric Ø3 mm circle. Finish the sketch, then select only the annulus between Ø3 mm and Ø5 mm and extrude it 1 mm outward in the positive X direction with a one-sided 0° Join extrusion. Do not extrude the inner disk and do not create a pattern in this stage—the circular pattern is the next stage. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 6 of 17
+
+Create a circular pattern of the raised annular bolt detail: use a feature circular pattern (pattern the extrusion feature itself, not sketch geometry or faces), select the 1 mm annular pad from the previous stage, set the pattern axis to the main shaft axis (the X axis), quantity 12, full 360° distribution with equal spacing. The result is twelve identical raised annular details arranged around the shaft's terminal face. This stage adds exactly one circular pattern feature and nothing else, keeping a single solid body.
+
+### Stage 7 of 17
+
+On the patterned terminal face from the previous stage, create one fully constrained, centered shaft-profile sketch. In global YZ coordinates, draw straight side segments at Z = −16 mm and Z = +16 mm, each extending from Y = −17 mm to Y = +17 mm. Connect the upper endpoints with a minor R22 mm arc bulging toward positive Y and the lower endpoints with a separate minor R22 mm arc bulging toward negative Y. Keep one closed profile with no center divider. Finish the sketch, then extrude that profile 100 mm outward in the positive X direction, one-sided, with 0° taper and Join. This stage ends with two distinct R22 curved shaft faces, adding exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 8 of 17
+
+On the 100 mm keyed shaft from the previous stage, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both face regions inside the Ø62 mm boundary—the keyed central region and its surrounding region—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be one complete Ø62 mm circular flange, one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 9 of 17
+
+On the Ø62 mm flange from the previous stage, create a new fully constrained sketch on the flange's exposed terminal face. Offset the Ø62 mm circular perimeter inward by 1 mm using a −1 mm sketch offset, producing exactly one centered Ø60 mm profile. Finish the sketch, then extrude the central Ø60 mm disk—not the surrounding annulus—1 mm outward in the positive X direction with a one-sided 0° Join extrusion. The result must be a solid raised Ø60 mm disk with no enclosed cavity, exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 10 of 17
+
+On the raised Ø60 mm end face from the previous stage, create a fully constrained sketch on that face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both regions inside the Ø62 mm boundary—the central Ø60 mm face and the surrounding Ø60-to-Ø62 mm annulus—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be a complete Ø62 mm circular end flange, exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 11 of 17
+
+Create a construction plane coincident with the flat positive-Z side face of the original untapered housing—the plane at global Z = 37.5 mm that contains the housing's two long parallel longitudinal edges. Any construction-plane method that produces a plane exactly coincident with that face is acceptable. Add nothing else in this stage: no sketch and no solid feature.
+
+### Stage 12 of 17
+
+On the construction plane you just created, make a fully constrained sketch. Draw exactly one Ø85 mm circle centered at the midpoint of the lower longitudinal edge of the original 100 mm housing section: global X = 50 mm, Y = −45 mm, Z = 37.5 mm. Finish the sketch, then extrude the circular profile symmetrically about that plane by 10.5 mm on each side, for 21 mm total thickness, with 0° taper and Join. The disk must span global Z = 27 mm to Z = 48 mm and remain part of the single body. This stage adds exactly one new sketch and one new extrusion feature.
+
+### Stage 13 of 17
+
+On the Ø85 mm side disk from the previous stage, create a fully constrained sketch on its negative-Z planar face at global Z = 27 mm. Use the existing straight lower housing edge to close the top of one support profile. Place two vertical sketch lines at global X = 30 mm and X = 70 mm, start both on the housing edge at Y = −45 mm, and extend each 30 mm toward negative Y to Y = −75 mm. Connect their lower endpoints with a minor R30 mm arc bulging toward negative Y. Finish the sketch, then extrude that one closed profile 35 mm from Z = 27 mm toward negative Z, ending at Z = −8 mm, with 0° taper and Join. This stage adds exactly one new sketch and one new extrusion feature, keeping a single solid body.
+
+### Stage 14 of 17
+
+On the joined lower support from the previous stage, create a fully constrained sketch on the support's axial end face at global X = 70 mm, perpendicular to the main X axis. Use the existing straight support edge between the exposed upper housing/support corner and the exposed lower support corner as the closing chord; do not assign an invented chord length. From the upper corner, draw a 25 mm top segment in the support-face horizontal direction, then connect its far endpoint to the existing lower corner with a minor R55 mm arc bulging outward. Finish the resulting closed curved gusset profile, then extrude that profile 40 mm in the negative X direction using a one-sided −40 mm distance, 0° taper, and Join. Stop before the trimming cut (that is the next stage), with exactly one new sketch, one new extrusion feature, and one solid body.
+
+### Stage 15 of 17
+
+Trim the lower support region outside the curved gusset: reuse the gusset sketch from the previous stage—select the remaining closed region between the gusset arc and the support outline (the lower region you did not extrude)—and extrude-cut it 40 mm in the negative X direction, one-sided −40 mm distance, 0° taper, operation Cut. Do not create a new sketch. The cut removes the support material outside the curved gusset so the support's end matches the gusset profile. This stage adds exactly one new cut feature and no sketch, keeping a single solid body.
+
+### Stage 16 of 17
+
+With the side disk and trimmed support complete, create a fully constrained sketch on the positive-Z outer planar face of the Ø85 mm side disk at global Z = 48 mm. Draw exactly one Ø30 mm circle concentric with the disk at global X = 50 mm and Y = −45 mm. Finish the sketch, then extrude-cut that profile 20 mm in the negative Z direction using a one-sided −20 mm distance and 0° taper. Do not use Through All and do not create the axial end-flange hole yet—that is the final stage. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+### Stage 17 of 17
+
+With the side-disk cut complete, create a fully constrained sketch on the exposed axial end face of the final Ø62 mm flange at global X = 296 mm. Draw exactly one Ø30 mm circle concentric with the main X axis and coincident with the end-face center. Finish the sketch, then extrude-cut that profile 20 mm in the negative X direction using a one-sided −20 mm distance and 0° taper. This must create the separate axial end-flange hole; do not add a second sketch or cut on the side disk. This stage adds exactly one new sketch and one new cut feature, keeping a single solid body.
+
+End state across all stages: exactly 13 new sketches, 15 new extrusion or cut features, one circular pattern feature, one construction plane, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above. Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_complete_curved_linkage/task.md

@@ -1,3 +1,53 @@
-# Complete curved two-socket Jaw linkage
+# Build the complete curved two-socket Jaw linkage
 
-Expert · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, build the complete mechanical linkage described below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, code, or another CAD program.
+
+## Starting state
+
+The supplied design is a clean parametric design in millimetres. It contains only the root component and Origin; it has no sketches, components, construction planes, features, or bodies.
+
+## Coordinate system and overall result
+
+Create one continuous solid body with three functional regions: a large primary socket end, a smooth curved bridge, and a smaller secondary socket end. These are regions of one joined part, not three separate components or bodies. Both socket axes are parallel to the global Y axis. Place the primary socket axis at global (X, Z) = (0, 0) mm and the secondary socket axis at global (X, Z) = (-350, 0) mm, giving exactly 350 mm center-to-center spacing.
+
+The completed part should occupy approximately X = -385 to 57.5 mm, Y = -20 to 51 mm, and Z = -57.5 to 62.5 mm. Small deviations caused by reasonable blends are acceptable, but preserve the two socket locations, their diameters, and the overall proportions.
+
+## Primary socket end
+
+1. Create a concentric circular base flange with an outside diameter of 115 mm and a nominal axial thickness of 12 mm.
+2. Add the raised primary cylindrical housing with a 90 mm outside diameter and 30 mm height above the flange.
+3. Form the upper stepped collar with approximately 60 mm outside diameter and 54 mm inside diameter.
+4. Create a central cylindrical opening of exactly 30 mm diameter along the global Y axis.
+5. Give the socket opening a rounded internal seat and a smooth rounded lip comparable to a revolved bearing seat. The exact spline, revolve profile, and small blend radii are not prescribed, but the result must remain concentric, smooth, and mechanically plausible.
+
+## Secondary socket end
+
+1. Center this socket exactly 350 mm in the negative global X direction from the primary socket.
+2. Create a 70 mm outside-diameter cylindrical housing with a nominal 42 mm axial height.
+3. Form its upper stepped collar with approximately 50 mm outside diameter and 45 mm inside diameter.
+4. Create a central cylindrical opening of exactly 30 mm diameter along the global Y axis.
+5. Add a rounded internal seat and lip that are visually and functionally consistent with the primary socket, while retaining the smaller outside proportions.
+
+## Curved bridge
+
+Join the two socket housings with a single smooth, tapered, curved solid bridge. A loft between suitable constrained profiles is a good approach, but an equivalent native Fusion construction is acceptable. The bridge must merge cleanly into both housings, remain one solid body, and have continuous, rounded transitions without abrupt block-like steps. It should be broader near the primary end and taper toward the secondary end.
+
+The exact bridge spline, loft rails, and profile control points are intentionally not specified. Match the reference's overall bowed centerline and envelope rather than attempting to infer a unique curve. Use fillets or equivalent native blends where helpful.
+
+## Primary flange annular pattern
+
+Create a 360-degree circular pattern of 18 nominal positions around the primary socket axis on an approximately 102.5 mm pitch-circle diameter. Each patterned feature is a 4 mm high annular tower with 9 mm outside diameter and 6 mm inside diameter, joined to the flange. The bridge overlaps part of the circular pattern; in the intended final solid, 13 annular towers remain exposed as distinct cylindrical rings while the covered positions merge into the bridge region. Preserve the regular angular spacing and concentric placement.
+
+## Design intent and acceptable variation
+
+- The final result must be exactly one visible solid body.
+- The two socket axes, 350 mm spacing, Ø30 openings, principal stepped diameters, and annular pattern are authoritative.
+- The bridge centerline, loft profiles, detailed revolved seat profiles, and small fillets are intentionally flexible. Diverse native Fusion constructions are acceptable when they produce the same functional layout and a close overall shape.
+- Keep features healthy and unsuppressed. Fully constrain sketches where practical and use a circular pattern rather than manually placing repeated towers when possible.
+- Do not create disconnected helper solids, separate components, mesh bodies, or surface-only results.
+
+## Completion requirements
+
+Leave the completed design open in Fusion and use the finish action when the task is complete. Do not use Save or Save As; the environment exports the open design automatically. Do not open or import any external CAD file, including another task seed, STEP file, or answer archive.
+
+Recommended interaction budget: up to 180 model turns, 600 action groups, and 3600 seconds.

tasks/jaw_se_05_long_keyed_shaft/task.md

@@ -1,3 +1,13 @@
 # Sketch and extrude the keyed shaft
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+## Required result
+
+Starting from the supplied patterned terminal face, create one fully constrained, centered shaft-profile sketch. In global YZ coordinates, draw straight side segments at Z = −16 mm and Z = +16 mm, each extending from Y = −17 mm to Y = +17 mm. Connect the upper endpoints with a minor R22 mm arc bulging toward positive Y and the lower endpoints with a separate minor R22 mm arc bulging toward negative Y. Keep one closed profile with no center divider. Finish the sketch, then extrude that profile 100 mm outward in the positive X direction, one-sided, with 0° taper and Join. Stop with two distinct R22 curved shaft faces, exactly one new sketch, one new extrusion feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_se_06_first_end_flange/task.md

@@ -1,3 +1,13 @@
 # Sketch and extrude the first end flange
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+## Required result
+
+Starting from the supplied 100 mm keyed shaft, create a fully constrained sketch on its exposed terminal face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both face regions inside the Ø62 mm boundary—the keyed central region and its surrounding region—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be one complete Ø62 mm circular flange, one new sketch, one new extrusion feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_se_07_raised_end_inset/task.md

@@ -1,3 +1,13 @@
 # Sketch and extrude the raised end inset
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+## Required result
+
+Starting from the supplied Ø62 mm flange whose earlier sketch already contains the corrected inward Ø60 mm offset, create a new fully constrained sketch on the flange's exposed terminal face. Offset the Ø62 mm circular perimeter inward by 1 mm using a −1 mm sketch offset, producing exactly one centered Ø60 mm profile. Finish the sketch, then extrude the central Ø60 mm disk—not the surrounding annulus—1 mm outward in the positive X direction with a one-sided 0° Join extrusion. The result must be a solid raised Ø60 mm disk with no enclosed cavity, exactly one new sketch, one new extrusion feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_se_08_final_end_flange/task.md

@@ -1,3 +1,13 @@
 # Sketch and extrude the final end flange
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+## Required result
+
+Starting from the supplied raised Ø60 mm end face, create a fully constrained sketch on that face. Draw exactly one Ø62 mm circle concentric with the main X axis and coincident with the sketch origin. Finish the sketch. Select both regions inside the Ø62 mm boundary—the central Ø60 mm face and the surrounding Ø60-to-Ø62 mm annulus—and extrude them together 10 mm outward in the positive X direction, one-sided, with 0° taper and Join. The result must be a complete Ø62 mm circular end flange, exactly one new sketch, one new extrusion feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_se_09_side_disk/task.md

@@ -1,3 +1,13 @@
 # Sketch and extrude the side disk
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+## Required result
+
+Starting from the supplied body and existing construction plane Plane1, create a fully constrained sketch on Plane1. Draw exactly one Ø85 mm circle centered at the midpoint of the lower longitudinal edge of the original 100 mm housing section: global X = 50 mm, Y = −45 mm, Z = 37.5 mm. Finish the sketch, then extrude the circular profile symmetrically about Plane1 by 10.5 mm on each side, for 21 mm total thickness, with 0° taper and Join. The disk must span global Z = 27 mm to Z = 48 mm and remain part of the single body. Stop with exactly one new sketch and one new extrusion feature.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_se_10_lower_support/task.md

@@ -1,3 +1,13 @@
 # Sketch and extrude the lower support
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+## Required result
+
+Starting from the supplied Ø85 mm side disk, create a fully constrained sketch on its negative-Z planar face at global Z = 27 mm. Use the existing straight lower housing edge to close the top of one support profile. Place two vertical sketch lines at global X = 30 mm and X = 70 mm, start both on the housing edge at Y = −45 mm, and extend each 30 mm toward negative Y to Y = −75 mm. Connect their lower endpoints with a minor R30 mm arc bulging toward negative Y. Finish the sketch, then extrude that one closed profile 35 mm from Z = 27 mm toward negative Z, ending at Z = −8 mm, with 0° taper and Join. Stop with exactly one new sketch, one new extrusion feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_se_11_added_gusset/task.md

@@ -1,3 +1,13 @@
 # Sketch and extrude the gusset
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+## Required result
+
+Starting from the supplied joined lower support, create a fully constrained sketch on the support's axial end face at global X = 70 mm, perpendicular to the main X axis. Use the existing straight support edge between the exposed upper housing/support corner and the exposed lower support corner as the closing chord; do not assign an invented chord length. From the upper corner, draw a 25 mm top segment in the support-face horizontal direction, then connect its far endpoint to the existing lower corner with a minor R55 mm arc bulging outward. Finish the resulting closed curved gusset profile, then extrude that profile 40 mm in the negative X direction using a one-sided −40 mm distance, 0° taper, and Join. Stop before the later trimming cut, with exactly one new sketch, one new extrusion feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_se_12_side_disk_hole/task.md

@@ -1,3 +1,13 @@
 # Sketch and cut the side-disk hole
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+## Required result
+
+Starting from the supplied completed side disk and trimmed support, create a fully constrained sketch on the positive-Z outer planar face of the Ø85 mm side disk at global Z = 48 mm. Draw exactly one Ø30 mm circle concentric with the disk at global X = 50 mm and Y = −45 mm. Finish the sketch, then extrude-cut that profile 20 mm in the negative Z direction using a one-sided −20 mm distance and 0° taper. Do not use Through All and do not create any axial end-flange hole. Stop with exactly one new sketch, one new cut feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/jaw_se_13_axial_end_flange_hole/task.md

@@ -1,3 +1,13 @@
 # Sketch and cut the axial end-flange hole
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the CAD task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the Fusion API, a terminal, or another CAD program.
+
+## Required result
+
+Starting from the supplied body with its completed side-disk cut, create a fully constrained sketch on the exposed axial end face of the final Ø62 mm flange at global X = 296 mm. Draw exactly one Ø30 mm circle concentric with the main X axis and coincident with the end-face center. Finish the sketch, then extrude-cut that profile 20 mm in the negative X direction using a one-sided −20 mm distance and 0° taper. This must create the separate axial end-flange hole; do not add a second sketch or cut on the side disk. Stop with exactly one new sketch, one new cut feature, and one solid body.
+
+## Completion requirements
+
+Finish the sketch and feature operations, leave the completed design open in Fusion, and do not add geometry or features not requested above.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/proc_connected_lines_14e1ddda38c3/task.md

@@ -1,3 +1,37 @@
 # Draw an open 4-segment orthogonal chain
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the sketch task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the API, or any external CAD program.
+
+## Starting state
+
+The supplied design is a clean parametric design in millimetres. It contains only the root component and Origin; it has no sketches, components, features, construction planes, or bodies.
+
+## Required result
+
+Create exactly one new 2D sketch on the YZ origin plane. Select that plane directly from the Origin folder when Fusion asks for the sketch plane.
+
+All coordinates below are local sketch coordinates in millimetres. X and Y refer to the axes displayed while editing the sketch, viewed normal to the selected sketch plane. They describe the required final geometry: establish them with dimensions and geometric constraints rather than relying on visual grid placement. Unless a requirement names a particular operation or constraint, any visible-UI construction sequence that produces the same final geometry is acceptable.
+
+1. Draw a regular, non-construction line from (-13, -19) mm to (-32, -19) mm.
+2. Draw a regular, non-construction line from (-32, -19) mm to (-32, -37) mm.
+3. Draw a regular, non-construction line from (-32, -37) mm to (-43, -37) mm.
+4. Draw a regular, non-construction line from (-43, -37) mm to (-43, -49) mm.
+
+## Constraints and design intent
+
+- Connect these points in order: (-13, -19) mm, (-32, -19) mm, (-32, -37) mm, (-43, -37) mm, (-43, -49) mm.
+- Every consecutive pair must share one truly coincident endpoint.
+- Keep exactly 4 regular line entities and leave the chain open.
+- The finished sketch must report that it is fully constrained. Use dimensions and geometric constraints as needed while preserving the exact geometry above.
+
+## Completion requirements
+
+- The final design must contain exactly 1 sketch and 0 solid or surface bodies.
+- The requested geometry must produce exactly 0 closed sketch profiles.
+- Use regular sketch geometry unless an entity is explicitly described as construction geometry.
+- Do not add extra sketches, curves, points, projected geometry, text, components, features, or bodies.
+- Finish the sketch and leave the completed design open in Fusion.
+
+Recommended interaction budget: 82 steps and 300 seconds.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/proc_polygon_6a15b2b2b55d/task.md

@@ -1,3 +1,42 @@
 # Draw a regular 8-sided polygon
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the sketch task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the API, or any external CAD program.
+
+## Starting state
+
+The supplied design is a clean parametric design in millimetres. It contains only the root component and Origin; it has no sketches, components, features, construction planes, or bodies.
+
+## Required result
+
+Create exactly one new 2D sketch on the YZ origin plane. Select that plane directly from the Origin folder when Fusion asks for the sketch plane.
+
+All coordinates below are local sketch coordinates in millimetres. X and Y refer to the axes displayed while editing the sketch, viewed normal to the selected sketch plane. They describe the required final geometry: establish them with dimensions and geometric constraints rather than relying on visual grid placement. Unless a requirement names a particular operation or constraint, any visible-UI construction sequence that produces the same final geometry is acceptable.
+
+1. Draw a regular, non-construction line from (3.520908, -10.571057) mm to (15.692446, 3.186364) mm.
+2. Draw a regular, non-construction line from (15.692446, 3.186364) mm to (14.571057, 21.520908) mm.
+3. Draw a regular, non-construction line from (14.571057, 21.520908) mm to (0.813636, 33.692446) mm.
+4. Draw a regular, non-construction line from (0.813636, 33.692446) mm to (-17.520908, 32.571057) mm.
+5. Draw a regular, non-construction line from (-17.520908, 32.571057) mm to (-29.692446, 18.813636) mm.
+6. Draw a regular, non-construction line from (-29.692446, 18.813636) mm to (-28.571057, 0.479092) mm.
+7. Draw a regular, non-construction line from (-28.571057, 0.479092) mm to (-14.813636, -11.692446) mm.
+8. Draw a regular, non-construction line from (-14.813636, -11.692446) mm to (3.520908, -10.571057) mm.
+
+## Constraints and design intent
+
+- Use Fusion's regular polygon geometry with exactly 8 perimeter sides.
+- Make the center exactly (-7, 11) mm and the circumradius exactly 24 mm.
+- Place the first radial vertex at an angle of exactly 296 degrees counterclockwise from the positive sketch X axis.
+- The center, circumradius, side count, and orientation are authoritative; displayed vertex decimals are derived values.
+- The finished sketch must report that it is fully constrained. Use dimensions and geometric constraints as needed while preserving the exact geometry above.
+
+## Completion requirements
+
+- The final design must contain exactly 1 sketch and 0 solid or surface bodies.
+- The requested geometry must produce exactly 1 closed sketch profile.
+- Use regular sketch geometry unless an entity is explicitly described as construction geometry.
+- Do not add extra sketches, curves, points, projected geometry, text, components, features, or bodies.
+- Finish the sketch and leave the completed design open in Fusion.
+
+Recommended interaction budget: 103 steps and 300 seconds.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/proc_spline_profile_29ee4d0d9bf2/task.md

@@ -1,3 +1,37 @@
 # Draw a closed profile with a 4-point fitted spline
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the sketch task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the API, or any external CAD program.
+
+## Starting state
+
+The supplied design is a clean parametric design in millimetres. It contains only the root component and Origin; it has no sketches, components, features, construction planes, or bodies.
+
+## Required result
+
+Create exactly one new 2D sketch on the XZ origin plane. Select that plane directly from the Origin folder when Fusion asks for the sketch plane.
+
+All coordinates below are local sketch coordinates in millimetres. X and Y refer to the axes displayed while editing the sketch, viewed normal to the selected sketch plane. They describe the required final geometry: establish them with dimensions and geometric constraints rather than relying on visual grid placement. Unless a requirement names a particular operation or constraint, any visible-UI construction sequence that produces the same final geometry is acceptable.
+
+1. Draw a regular, non-construction fitted spline through these fit points in order: (-25, 0) mm, (-8.333333, 24) mm, (8.333333, 24) mm, (25, 0) mm. Use Fusion's default fitted-spline shape and do not add tangent handles.
+2. Draw a regular, non-construction line from (25, 0) mm to (4, -24) mm.
+3. Draw a regular, non-construction line from (4, -24) mm to (-25, 0) mm.
+
+## Constraints and design intent
+
+- Create exactly one fitted spline by placing these 4 fit points once and in order: (-25, 0) mm, (-8.333333, 24) mm, (8.333333, 24) mm, (25, 0) mm.
+- From the final spline point draw one line to (4, -24) mm and a second line back to the first spline point.
+- Do not edit tangent handles, convert the spline type, insert fit points, or drag the generated curve after placement.
+- Make the three curve junctions coincident so there is exactly one closed profile.
+- Full constraint is not required for this task; do not alter the requested geometry merely to force a fully-constrained status.
+
+## Completion requirements
+
+- The final design must contain exactly 1 sketch and 0 solid or surface bodies.
+- The requested geometry must produce exactly 1 closed sketch profile.
+- Use regular sketch geometry unless an entity is explicitly described as construction geometry.
+- Do not add extra sketches, curves, points, projected geometry, text, components, features, or bodies.
+- Finish the sketch and leave the completed design open in Fusion.
+
+Recommended interaction budget: 95 steps and 300 seconds.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/proc_spline_profile_617986cd5abf/task.md

@@ -1,3 +1,37 @@
 # Draw a closed profile with a 4-point fitted spline
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the sketch task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the API, or any external CAD program.
+
+## Starting state
+
+The supplied design is a clean parametric design in millimetres. It contains only the root component and Origin; it has no sketches, components, features, construction planes, or bodies.
+
+## Required result
+
+Create exactly one new 2D sketch on the YZ origin plane. Select that plane directly from the Origin folder when Fusion asks for the sketch plane.
+
+All coordinates below are local sketch coordinates in millimetres. X and Y refer to the axes displayed while editing the sketch, viewed normal to the selected sketch plane. They describe the required final geometry: establish them with dimensions and geometric constraints rather than relying on visual grid placement. Unless a requirement names a particular operation or constraint, any visible-UI construction sequence that produces the same final geometry is acceptable.
+
+1. Draw a regular, non-construction fitted spline through these fit points in order: (-34, 0) mm, (-11.333333, 17) mm, (11.333333, 32) mm, (34, 0) mm. Use Fusion's default fitted-spline shape and do not add tangent handles.
+2. Draw a regular, non-construction line from (34, 0) mm to (6, -20) mm.
+3. Draw a regular, non-construction line from (6, -20) mm to (-34, 0) mm.
+
+## Constraints and design intent
+
+- Create exactly one fitted spline by placing these 4 fit points once and in order: (-34, 0) mm, (-11.333333, 17) mm, (11.333333, 32) mm, (34, 0) mm.
+- From the final spline point draw one line to (6, -20) mm and a second line back to the first spline point.
+- Do not edit tangent handles, convert the spline type, insert fit points, or drag the generated curve after placement.
+- Make the three curve junctions coincident so there is exactly one closed profile.
+- Full constraint is not required for this task; do not alter the requested geometry merely to force a fully-constrained status.
+
+## Completion requirements
+
+- The final design must contain exactly 1 sketch and 0 solid or surface bodies.
+- The requested geometry must produce exactly 1 closed sketch profile.
+- Use regular sketch geometry unless an entity is explicitly described as construction geometry.
+- Do not add extra sketches, curves, points, projected geometry, text, components, features, or bodies.
+- Finish the sketch and leave the completed design open in Fusion.
+
+Recommended interaction budget: 95 steps and 300 seconds.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.

tasks/proc_spline_profile_9d745c7e4ed3/task.md

@@ -1,3 +1,37 @@
 # Draw a closed profile with a 6-point fitted spline
 
-Hard · Visible UI only · Match [`answer.f3d`](./answer.f3d).
+Using only Autodesk Fusion's visible user interface, complete the sketch task below. Work in the root component and use millimetres. Do not use scripts, add-ins, the API, or any external CAD program.
+
+## Starting state
+
+The supplied design is a clean parametric design in millimetres. It contains only the root component and Origin; it has no sketches, components, features, construction planes, or bodies.
+
+## Required result
+
+Create exactly one new 2D sketch on the XY origin plane. Select that plane directly from the Origin folder when Fusion asks for the sketch plane.
+
+All coordinates below are local sketch coordinates in millimetres. X and Y refer to the axes displayed while editing the sketch, viewed normal to the selected sketch plane. They describe the required final geometry: establish them with dimensions and geometric constraints rather than relying on visual grid placement. Unless a requirement names a particular operation or constraint, any visible-UI construction sequence that produces the same final geometry is acceptable.
+
+1. Draw a regular, non-construction fitted spline through these fit points in order: (-30, 0) mm, (-18, 30) mm, (-6, 23) mm, (6, 31) mm, (18, 15) mm, (30, 0) mm. Use Fusion's default fitted-spline shape and do not add tangent handles.
+2. Draw a regular, non-construction line from (30, 0) mm to (-6, -19) mm.
+3. Draw a regular, non-construction line from (-6, -19) mm to (-30, 0) mm.
+
+## Constraints and design intent
+
+- Create exactly one fitted spline by placing these 6 fit points once and in order: (-30, 0) mm, (-18, 30) mm, (-6, 23) mm, (6, 31) mm, (18, 15) mm, (30, 0) mm.
+- From the final spline point draw one line to (-6, -19) mm and a second line back to the first spline point.
+- Do not edit tangent handles, convert the spline type, insert fit points, or drag the generated curve after placement.
+- Make the three curve junctions coincident so there is exactly one closed profile.
+- Full constraint is not required for this task; do not alter the requested geometry merely to force a fully-constrained status.
+
+## Completion requirements
+
+- The final design must contain exactly 1 sketch and 0 solid or surface bodies.
+- The requested geometry must produce exactly 1 closed sketch profile.
+- Use regular sketch geometry unless an entity is explicitly described as construction geometry.
+- Do not add extra sketches, curves, points, projected geometry, text, components, features, or bodies.
+- Finish the sketch and leave the completed design open in Fusion.
+
+Recommended interaction budget: 95 steps and 300 seconds.
+
+Do not use Save or Save As. Do not open or import any external CAD file, including another task seed or answer. The environment exports the open design automatically; use the finish action when the task is complete.