diff --git a/docs/source/image_tool.py b/docs/source/image_tool.py
new file mode 100644
index 00000000..26355df0
--- /dev/null
+++ b/docs/source/image_tool.py
@@ -0,0 +1,87 @@
+from pprint import pprint
+
+from PIL import Image
+
+from effectful.handlers.llm import Agent, Template, Tool
+from effectful.handlers.llm.completions import (
+    LiteLLMProvider,
+    RetryLLMHandler,
+    completion,
+)
+from effectful.ops.semantics import fwd, handler
+
+
+class ImageTools(Agent):
+    """You are an image processing agent."""
+
+    def __init__(self):
+        self._image_to_handle = {}
+        self._handle_to_image = {}
+
+    def _encode(self, image: Image) -> int:
+        image_id = id(image)
+        handle = self._image_to_handle.get(image_id, None)
+        if handle is not None:
+            return handle
+
+        handle = len(self._image_to_handle)
+        self._image_to_handle[image_id] = handle
+
+        assert handle not in self._handle_to_image
+        self._handle_to_image[handle] = image
+        return handle
+
+    def _decode(self, image_handle: int) -> Image:
+        return self._handle_to_image[image_handle]
+
+    @Tool.define
+    def rotate(self, image: int, angle: float) -> int:
+        """Returns a rotated copy of this image. The copy is rotated by `angle`
+        degrees counterclockwise around the image center.
+
+        """
+        return self._encode(self._decode(image).rotate(angle))
+
+    @Tool.define
+    def concat_horiz(self, i1_h: int, i2_h: int) -> int:
+        """Concatenates two images horizontally. The larger image will be
+        cropped to the height of the smaller image.
+
+        """
+        i1 = self._decode(i1_h)
+        i2 = self._decode(i2_h)
+        i3 = Image.new("RGB", (i1.width + i2.width, min(i1.height, i2.height)))
+        i3.paste(i1, (0, 0))
+        i3.paste(i2, (i1.width, 0))
+        return self._encode(i3)
+
+    @Template.define
+    def _rotate_and_concat(self, i: int) -> int:
+        """Create an image consisting of four copies of the image {i}
+        concatenated horizontally. Each copy should be rotated 90 degrees from
+        the previous.
+
+        """
+        pass  # type: ignore
+
+    def rotate_and_concat(self, i: Image) -> Image:
+        return self._decode(self._rotate_and_concat(self._encode(i)))
+
+
+def log_completion(*args, **kwargs):
+    pprint((args, kwargs))
+    return fwd()
+
+
+if __name__ == "__main__":
+    image_agent = ImageTools()
+    img = Image.open("_static/img/chirho_logo_wide.png")
+
+    image_agent._rotate_and_concat.tools
+    provider = LiteLLMProvider(model="gpt-5-mini")
+    with (
+        handler(provider),
+        handler({completion: log_completion}),
+        handler(RetryLLMHandler()),
+    ):
+        image_agent.rotate_and_concat(img).show()