Load HuggingFace Tool (#4475)

# Add option to `load_huggingface_tool`

Expose a method to load a huggingface Tool from the HF hub

---------

Co-authored-by: Dev 2049 <dev.dev2049@gmail.com>

docs/modules/agents/tools/examples/huggingface_tools.ipynb

@@ -0,0 +1,102 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "40a27d3c-4e5c-4b96-b290-4c49d4fd7219",
+   "metadata": {},
+   "source": [
+    "## HuggingFace Tools\n",
+    "\n",
+    "[Huggingface Tools](https://huggingface.co/docs/transformers/v4.29.0/en/custom_tools) supporting text I/O can be\n",
+    "loaded directly using the `load_huggingface_tool` function."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "d1055b75-362c-452a-b40d-c9a359706a3a",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Requires transformers>=4.29.0 and huggingface_hub>=0.14.1\n",
+    "!pip install --uprade transformers huggingface_hub > /dev/null"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "id": "f964bb45-fba3-4919-b022-70a602ed4354",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "model_download_counter: This is a tool that returns the most downloaded model of a given task on the Hugging Face Hub. It takes the name of the category (such as text-classification, depth-estimation, etc), and returns the name of the checkpoint\n"
+     ]
+    }
+   ],
+   "source": [
+    "from langchain.agents import load_huggingface_tool\n",
+    "\n",
+    "tool = load_huggingface_tool(\"lysandre/hf-model-downloads\")\n",
+    "\n",
+    "print(f\"{tool.name}: {tool.description}\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "id": "641d9d79-95bb-469d-b40a-50f37375de7f",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "'facebook/bart-large-mnli'"
+      ]
+     },
+     "execution_count": 2,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "tool.run(\"text-classification\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "88724222-7c10-4aff-8713-751911dc8b63",
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.11.2"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

langchain/agents/__init__.py

@@ -23,7 +23,11 @@ from langchain.agents.agent_types import AgentType
 from langchain.agents.conversational.base import ConversationalAgent
 from langchain.agents.conversational_chat.base import ConversationalChatAgent
 from langchain.agents.initialize import initialize_agent
-from langchain.agents.load_tools import get_all_tool_names, load_tools
+from langchain.agents.load_tools import (
+    get_all_tool_names,
+    load_huggingface_tool,
+    load_tools,
+)
 from langchain.agents.loading import load_agent
 from langchain.agents.mrkl.base import MRKLChain, ZeroShotAgent
 from langchain.agents.react.base import ReActChain, ReActTextWorldAgent
@@ -61,6 +65,7 @@ __all__ = [
     "get_all_tool_names",
     "initialize_agent",
     "load_agent",
+    "load_huggingface_tool",
     "load_tools",
     "tool",
 ]

langchain/agents/load_tools.py

@@ -296,6 +296,40 @@ def _handle_callbacks(
     return callbacks
 
 
+def load_huggingface_tool(
+    task_or_repo_id: str,
+    model_repo_id: Optional[str] = None,
+    token: Optional[str] = None,
+    remote: bool = False,
+    **kwargs: Any,
+) -> BaseTool:
+    try:
+        from transformers import load_tool
+    except ImportError:
+        raise ValueError(
+            "HuggingFace tools require the libraries `transformers>=4.29.0`"
+            " and `huggingface_hub>=0.14.1` to be installed."
+            " Please install it with"
+            " `pip install --upgrade transformers huggingface_hub`."
+        )
+    hf_tool = load_tool(
+        task_or_repo_id,
+        model_repo_id=model_repo_id,
+        token=token,
+        remote=remote,
+        **kwargs,
+    )
+    outputs = hf_tool.outputs
+    if set(outputs) != {"text"}:
+        raise NotImplementedError("Multimodal outputs not supported yet.")
+    inputs = hf_tool.inputs
+    if set(inputs) != {"text"}:
+        raise NotImplementedError("Multimodal inputs not supported yet.")
+    return Tool.from_function(
+        hf_tool.__call__, name=hf_tool.name, description=hf_tool.description
+    )
+
+
 def load_tools(
     tool_names: List[str],
     llm: Optional[BaseLanguageModel] = None,

tests/unit_tests/agents/test_public_api.py

@@ -30,6 +30,7 @@ _EXPECTED = [
     "get_all_tool_names",
     "initialize_agent",
     "load_agent",
+    "load_huggingface_tool",
     "load_tools",
     "tool",
 ]