Small working demo that can draw boxes on a canvas

The idea is that you can write a small amount of JavaScript that reads the
JSON and renders in an HTML5 canvas, or some Python that renders it in Tkinter,
or anything else that strikes your fancy.

I would like to use this to draw diagrams representing the stack and
memory layout for an interpreter, to be used in internal docs.

python/examples/drawing/__init__.py

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+# Let's draw some diagrams
+

python/examples/drawing/demo.py

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+import asyncio
+import json
+import sys
+from typing import Any
+
+import schema as drawing
+from dotenv import dotenv_values
+
+from typechat import Success, Failure, TypeChatJsonTranslator, TypeChatValidator, create_language_model, process_requests
+
+
+async def main(file_path: str | None):
+    env_vals = dotenv_values()
+    model = create_language_model(env_vals)
+    validator = TypeChatValidator(drawing.Drawing)
+    translator = TypeChatJsonTranslator(model, validator, drawing.Drawing)
+    print(translator._schema_str)
+
+    async def request_handler(message: str):
+        result: Success[drawing.Drawing] | Failure = await translator.translate(message)
+        if isinstance(result, Failure):
+            print(result.message)
+        else:
+            value = result.value
+            print(json.dumps(value, indent=2))
+            if any(item["type"] == "Unknown" for item in value["items"]):
+                print("I did not understand the following")
+                for item in value["items"]:
+                    if item["type"] == "Unknown":
+                        print(item["text"])
+
+    await process_requests("~> ", file_path, request_handler)
+
+
+if __name__ == "__main__":
+    file_path = sys.argv[1] if len(sys.argv) == 2 else None
+    asyncio.run(main(file_path))

python/examples/drawing/schema.py

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+"""TypeChat schema for simple line drawings."""
+
+
+from typing_extensions import Literal, NotRequired, TypedDict, Annotated, Doc
+
+
+class Style(TypedDict):
+    type: Literal["Style"]
+    corners: Literal["rounded", "sharp"]
+    # We'll add things like line thickness, color, fill, etc. later
+
+
+class Box(TypedDict):
+    """A rectangular box.
+
+    The coordinate system has origin top left, x points right, y points down.
+    Measurements are in pixels.
+
+    There can also be text in the box. There are optional style properties.
+
+    """
+    type: Literal["Box"]
+    x: Annotated[int, Doc("Top left corner coordinates")]
+    y: int
+    width: Annotated[int, Doc("Size of the box")]
+    height: int
+    text: Annotated[str, Doc("Text centered in the box")]
+    style: Annotated[Style | None, Doc("Box drawing style (optional)")]
+
+
+class UnknownText(TypedDict):
+    """
+    Use this type for input that match nothing else
+    """
+
+    type: Literal["Unknown"]
+    text: Annotated[str, Doc("The text that wasn't understood")]
+
+
+class Drawing(TypedDict):
+    """
+    A drawing is a list of boxes. (We'll add other elements later, like arrows.)
+    """
+    items: list[Box | UnknownText]