docs: Add P2 duplicate report content bug

Root cause identified: MagenticFinalResultEvent and WorkflowOutputEvent
emit full report content that was already streamed. No deduplication exists.

This is a STACK BUG, not a model limitation. The fix involves tracking
streamed content length and emitting minimal completion message.

Also moves archived P1/P2 bugs to archive folder.

docs/bugs/ACTIVE_BUGS.md

@@ -9,6 +9,19 @@
 
 ## Currently Active Bugs
 
+### P2 - Duplicate Report Content in Output
+
+**File:** `docs/bugs/P2_DUPLICATE_REPORT_CONTENT.md`
+**Status:** OPEN - UX Bug
+
+**Problem:** The final research report appears twice in the UI - once as streaming content, then again as a complete event. This is a **stack bug**, not a model issue.
+
+**Root Cause:** Both `MagenticFinalResultEvent` and `WorkflowOutputEvent` emit the full report content that was already streamed. No deduplication exists.
+
+**Recommended Fix:** Track streamed content length in orchestrator; emit minimal "Research complete." message instead of repeating content.
+
+---
+
 ### P3 - Progress Bar Positioning in ChatInterface
 
 **File:** `docs/bugs/P3_PROGRESS_BAR_POSITIONING.md`

docs/bugs/P2_DUPLICATE_REPORT_CONTENT.md

@@ -0,0 +1,221 @@
+# P2 Bug: Duplicate Report Content in Output
+
+**Date**: 2025-12-03
+**Status**: OPEN
+**Severity**: P2 (UX - Duplicate content confuses users)
+**Component**: `src/orchestrators/advanced.py` + `src/app.py`
+
+---
+
+## Symptom
+
+The final research report appears **twice** in the UI output:
+1. First as streaming content (with `📡 **STREAMING**:` prefix)
+2. Then again as a complete event (without prefix)
+
+Example:
+```
+📡 **STREAMING**:
+### Summary of Drugs and Mechanisms of Action
+...
+### Conclusion
+Post-menopausal women experiencing libido issues can benefit from...
+### Recommendations
+- Estrogen Therapy: Effective in enhancing...
+
+Based on the information gathered, we have identified...   <-- DUPLICATE STARTS
+### Summary of Drugs and Mechanisms of Action
+...
+### Conclusion
+Post-menopausal women experiencing libido issues can benefit from...
+### Recommendations
+- Estrogen Therapy: Effective in enhancing...
+```
+
+---
+
+## Root Cause Analysis
+
+### Event Flow (Current - Buggy)
+
+```
+1. Reporter Agent streams content
+   └─ MagenticAgentDeltaEvent × N
+      └─ Each yields AgentEvent(type="streaming", message=delta)
+      └─ app.py: streaming_buffer += event.message
+      └─ User sees: "📡 **STREAMING**: [content building up]"
+
+2. Reporter Agent completes
+   └─ MagenticAgentMessageEvent
+      └─ Yields truncated completion: "reporter: [first 200 chars]..."
+      └─ app.py: flushes streaming_buffer to response_parts
+
+3. Workflow ends
+   └─ MagenticFinalResultEvent OR WorkflowOutputEvent
+      └─ Contains FULL report content (same as streaming)
+      └─ Yields AgentEvent(type="complete", message=FULL_CONTENT)
+      └─ app.py: appends event.message to response_parts
+      └─ User sees: [SAME CONTENT AGAIN]
+```
+
+### Bug Location
+
+**`src/orchestrators/advanced.py` lines 532-552:**
+```python
+elif isinstance(event, MagenticFinalResultEvent):
+    text = self._extract_text(event.message) if event.message else "No result"
+    return AgentEvent(
+        type="complete",
+        message=text,  # <-- FULL content, already streamed
+        ...
+    )
+
+elif isinstance(event, WorkflowOutputEvent):
+    if event.data:
+        text = self._extract_text(event.data)
+        return AgentEvent(
+            type="complete",
+            message=text,  # <-- FULL content, already streamed
+            ...
+        )
+```
+
+**`src/app.py` lines 229-232:**
+```python
+if event.type == "complete":
+    response_parts.append(event.message)  # <-- Appends duplicate
+    yield "\n\n".join(response_parts)
+```
+
+### Why It Happens
+
+1. **Streaming events** yield the full report character-by-character
+2. **Final events** (`MagenticFinalResultEvent`, `WorkflowOutputEvent`) contain the same full content
+3. **No deduplication** exists between streamed content and final event content
+4. **app.py appends both** to the output
+
+---
+
+## Impact
+
+| Aspect | Impact |
+|--------|--------|
+| UX | Report appears twice, looks buggy |
+| Token usage | Renders same content twice |
+| Trust | Users may think system is broken |
+
+---
+
+## Proposed Fix Options
+
+### Option 1: Skip Complete Event if Content Matches Streaming (Recommended)
+
+**Location**: `src/app.py` lines 229-232
+
+```python
+if event.type == "complete":
+    # Skip if content matches what we already streamed
+    streaming_content = next(
+        (p.replace("📡 **STREAMING**: ", "") for p in response_parts if p.startswith("📡 **STREAMING**:")),
+        None
+    )
+    if streaming_content and event.message.strip() == streaming_content.strip():
+        continue  # Skip duplicate
+    response_parts.append(event.message)
+    yield "\n\n".join(response_parts)
+```
+
+**Pros**: Simple, targets exact issue
+**Cons**: String comparison may be fragile
+
+### Option 2: Track Streamed Content Hash
+
+**Location**: `src/app.py`
+
+```python
+streaming_hash = None
+...
+if streaming_buffer:
+    streaming_hash = hash(streaming_buffer.strip())
+    response_parts.append(f"📡 **STREAMING**: {streaming_buffer}")
+    streaming_buffer = ""
+...
+if event.type == "complete":
+    if streaming_hash and hash(event.message.strip()) == streaming_hash:
+        continue  # Skip duplicate
+    response_parts.append(event.message)
+```
+
+**Pros**: More robust comparison
+**Cons**: Hash collision possible (unlikely)
+
+### Option 3: Don't Emit Complete Event Content from Orchestrator
+
+**Location**: `src/orchestrators/advanced.py` lines 532-552
+
+Replace full content with summary:
+```python
+elif isinstance(event, MagenticFinalResultEvent):
+    return AgentEvent(
+        type="complete",
+        message="Research complete.",  # Don't repeat content
+        data={"iterations": iteration},
+        iteration=iteration,
+    )
+```
+
+**Pros**: Clean separation of streaming vs completion
+**Cons**: Loses fallback if streaming failed
+
+### Option 4: Flag-Based Deduplication in Orchestrator
+
+**Location**: `src/orchestrators/advanced.py`
+
+Track if substantial streaming occurred:
+```python
+has_substantial_streaming = len(current_message_buffer) > 100
+
+# In _process_event for final events:
+if has_substantial_streaming:
+    return AgentEvent(
+        type="complete",
+        message="Research complete.",  # Don't repeat
+        ...
+    )
+```
+
+---
+
+## Recommended Fix
+
+**Option 3** is cleanest - the orchestrator should not re-emit content that was already streamed.
+
+**Implementation**:
+1. Track `streamed_report_length` in the run loop
+2. If substantial content was streamed (>500 chars), emit minimal complete message
+3. If no streaming occurred, emit full content as fallback
+
+---
+
+## Files Involved
+
+| File | Role |
+|------|------|
+| `src/orchestrators/advanced.py:532-552` | Emits duplicate complete events |
+| `src/app.py:229-232` | Appends duplicate to output |
+
+---
+
+## Test Plan
+
+1. Run Free Tier query: "What drugs improve female libido post-menopause?"
+2. Verify report appears ONCE (with streaming prefix)
+3. Verify `complete` event does NOT repeat content
+4. Verify fallback works if streaming fails
+
+---
+
+## Related
+
+- **Not related to model quality** - This is a stack bug, not model limitation
+- P1 Free Tier fix (PR fix/P1-free-tier) enabled streaming, exposing this bug