ToCode: post #6024 — TG.ME

uv run main.py

cd frontend
npm run dev

class ChatRequest(BaseModel):
    message: str
    canvas: CanvasState
    # Opaque pydantic-ai message history, exactly as returned by the previous
    # /api/chat response. Empty on a fresh page load.
    history: list[Any] = Field(default_factory=list)
    
class CanvasState(BaseModel):
    """The full canvas: its dimensions plus every shape on it."""

    width: int = CANVAS_WIDTH
    height: int = CANVAS_HEIGHT
    shapes: list[Shape] = Field(default_factory=list)    
    
class Shape(BaseModel):
    """A single shape placed on the canvas."""

    # Re-validate on assignment so the tools' `shape.size = ...` mutations go
    # through the same clamp as construction (keeps server + browser in sync).
    model_config = ConfigDict(validate_assignment=True)

    id: str
    type: ShapeType
    x: int = Field(description="Left position in pixels (0 = left edge).")
    y: int = Field(description="Top position in pixels (0 = top edge).")
    size: int = Field(default=DEFAULT_SHAPE_SIZE, description="Width/height in pixels.")
    color: str = Field(default=DEFAULT_SHAPE_COLOR, description="CSS color, e.g. '#ff0000'.")

    @field_validator("size")
    @classmethod
    def _clamp_size(cls, value: int) -> int:
        # Mirror the frontend store: never smaller than MIN_SHAPE_SIZE.
        return max(MIN_SHAPE_SIZE, value)

    @agent.instructions
    def add_canvas_state(ctx: RunContext[PainterDeps]) -> str:
        canvas = ctx.deps.canvas
        return (
            f"Canvas size: {canvas.width}x{canvas.height} pixels.\n"
            f"Current canvas state (JSON):\n{canvas.model_dump_json(indent=2)}"
        )

@agent.tool
async def add_shape(
    ctx: RunContext[PainterDeps],
    type: ShapeType,
    x: int,
    y: int,
    size: int = DEFAULT_SHAPE_SIZE,
    color: str = DEFAULT_SHAPE_COLOR,
) -> str:
    """Add a new shape to the canvas. Returns the new shape's id."""
    shape = Shape(id=uuid.uuid4().hex, type=type, x=x, y=y, size=size, color=color)
    ctx.deps.canvas.shapes.append(shape)
    return f"Added {type} (id={shape.id}) at ({x}, {y})."

@agent.tool
async def recolor_shape(ctx: RunContext[PainterDeps], id: str, color: str) -> str: