Update app.py

app.py

@@ -816,6 +816,7 @@ class ChessAnalysisInput(BaseModel):
     image_path: str = Field(description="Path to chess board image file")
     description: str = Field(description="Any additional context about the position (optional)", default="")
 
+@tool(args_schema=ChessAnalysisInput)
 @tool(args_schema=ChessAnalysisInput)
 def analyze_chess_position(image_path: str, description: str = "") -> str:
     """
@@ -832,6 +833,10 @@ def analyze_chess_position(image_path: str, description: str = "") -> str:
     - An image file shows a chess board
     - Need to find the best move in a position
     
+    Args:
+        image_path: Path to chess board image
+        description: The full question text - IMPORTANT for determining whose turn it is!
+    
     Returns: Best move in algebraic notation (e.g., "Qh5", "Nf6+", "Rd5")
     """
     if not image_path:
@@ -879,27 +884,49 @@ def analyze_chess_position(image_path: str, description: str = "") -> str:
             temperature=0
         )
         
-        fen_prompt = """Analyze this chess board image and provide the position in FEN notation.
+        # Check if the question explicitly states whose turn it is
+        whose_turn = None
+        if description:
+            desc_lower = description.lower()
+            if "black" in desc_lower and ("turn" in desc_lower or "move" in desc_lower):
+                whose_turn = "b"
+            elif "white" in desc_lower and ("turn" in desc_lower or "move" in desc_lower):
+                whose_turn = "w"
+        
+        fen_prompt = f"""Analyze this chess board image and provide the position in FEN notation.
 
 CRITICAL INSTRUCTIONS:
 1. Carefully identify each piece:
    - White pieces (UPPERCASE): K=King, Q=Queen, R=Rook, B=Bishop, N=Knight, P=Pawn
    - Black pieces (lowercase): k, q, r, b, n, p
 
-2. Read the board from rank 8 (top) to rank 1 (bottom), left to right
+2. BOARD ORIENTATION - This is CRITICAL:
+   - In chess diagrams, the board is shown from the perspective of the player to move
+   - Look at the BOTTOM rank (closest to viewer):
+     * If bottom pieces are BLACK (lowercase in FEN) → Black to move → active color = 'b'
+     * If bottom pieces are WHITE (uppercase in FEN) → White to move → active color = 'w'
+   - The rank labels (1-8) on the side can help:
+     * If rank 8 is at bottom and rank 1 at top → Black's perspective → use 'b'
+     * If rank 1 is at bottom and rank 8 at top → White's perspective → use 'w'
+   {"- OVERRIDE: The question explicitly states BLACK's turn, so use 'b'" if whose_turn == "b" else ""}
+   {"- OVERRIDE: The question explicitly states WHITE's turn, so use 'w'" if whose_turn == "w" else ""}
+
+3. FEN Format (read from rank 8 to rank 1, left to right):
    - Use numbers (1-8) for consecutive empty squares
    - Use '/' to separate ranks
+   - IMPORTANT: Always write FEN from White's perspective (rank 8 first, rank 1 last)
+   - But set the active_color based on whose perspective the board shows
 
-3. Determine whose turn it is:
-   - Look for text like "Black to move" or "White to move"
-   - If unclear, analyze the position context
-   - Return 'w' for white, 'b' for black
-
-4. Return ONLY the FEN string in this format:
+4. Return ONLY the FEN string in this exact format:
    piece_placement active_color castling en_passant halfmove fullmove
-
+   
 Example: rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
 
+DOUBLE-CHECK:
+- Did you identify whose pieces are at the BOTTOM of the board?
+- Did you set active_color correctly based on board orientation?
+- Did you write piece_placement from rank 8 to rank 1?
+
 Return ONLY the FEN string, nothing else."""
         
         message = HumanMessage(
@@ -931,6 +958,40 @@ Return ONLY the FEN string, nothing else."""
         
         print(f"✓ Extracted FEN: {fen}")
         
+        # Override the turn indicator if we know from the question
+        if whose_turn:
+            fen_parts = fen.split()
+            if len(fen_parts) >= 2:
+                old_turn = fen_parts[1]
+                fen_parts[1] = whose_turn
+                fen = ' '.join(fen_parts)
+                print(f"🔄 Corrected turn from '{old_turn}' to '{whose_turn}' based on question")
+                print(f"✓ Corrected FEN: {fen}")
+        
+        # Additional verification: Check if board orientation matches turn
+        # In FEN, rank 8 is first, rank 1 is last
+        # If bottom of image shows black pieces, it's black's turn
+        fen_parts = fen.split()
+        piece_placement = fen_parts[0]
+        active_color = fen_parts[1] if len(fen_parts) > 1 else 'w'
+        
+        # Get last rank (rank 1 in FEN, which is bottom if white's perspective)
+        ranks = piece_placement.split('/')
+        rank_1 = ranks[-1]  # Last rank in FEN
+        rank_8 = ranks[0]   # First rank in FEN
+        
+        # Check which color dominates bottom rank
+        # If showing from black's perspective, rank 8 should be at bottom
+        # and active color should be 'b'
+        black_pieces_in_rank8 = sum(1 for c in rank_8 if c.islower() and c.isalpha())
+        white_pieces_in_rank8 = sum(1 for c in rank_8 if c.isupper() and c.isalpha())
+        
+        if black_pieces_in_rank8 > white_pieces_in_rank8 and active_color == 'w':
+            print(f"⚠️ Warning: Rank 8 has more black pieces, likely black's perspective")
+            print(f"   Changing active color from 'w' to 'b'")
+            fen_parts[1] = 'b'
+            fen = ' '.join(fen_parts)
+        
         # ====================================================================
         # STEP 2: Validate FEN with python-chess
         # ====================================================================