tool rendering (#10786)

libs/langchain/langchain/tools/render.py

@@ -0,0 +1,33 @@
+from typing import List
+
+from langchain.tools.base import BaseTool
+
+
+def render_text_description(tools: List[BaseTool]) -> str:
+    """Render the tool name and description in plain text.
+
+    Output will be in the format of:
+
+    ```
+    search: This tool is used for search
+    calculator: This tool is used for math
+    ```
+    """
+    return "\n".join([f"{tool.name}: {tool.description}" for tool in tools])
+
+
+def render_text_description_and_args(tools: List[BaseTool]) -> str:
+    """Render the tool name, description, and args in plain text.
+
+    Output will be in the format of:
+
+    ```
+    search: This tool is used for search, args: {"query": {"type": "string"}}
+    calculator: This tool is used for math, args: {"expression": {"type": "string"}}
+    ```
+    """
+    tool_strings = []
+    for tool in tools:
+        args_schema = str(tool.args)
+        tool_strings.append(f"{tool.name}: {tool.description}, args: {args_schema}")
+    return "\n".join(tool_strings)

libs/langchain/tests/unit_tests/tools/test_render.py

@@ -0,0 +1,42 @@
+from typing import List
+
+import pytest
+
+from langchain.tools.base import BaseTool, tool
+from langchain.tools.render import (
+    render_text_description,
+    render_text_description_and_args,
+)
+
+
+@tool
+def search(query: str) -> str:
+    """Lookup things online."""
+    return "foo"
+
+
+@tool
+def calculator(expression: str) -> str:
+    """Do math."""
+    return "bar"
+
+
+@pytest.fixture
+def tools() -> List[BaseTool]:
+    return [search, calculator]  # type: ignore
+
+
+def test_render_text_description(tools: List[BaseTool]) -> None:
+    tool_string = render_text_description(tools)
+    expected_string = """search: search(query: str) -> str - Lookup things online.
+calculator: calculator(expression: str) -> str - Do math."""
+    assert tool_string == expected_string
+
+
+def test_render_text_description_and_args(tools: List[BaseTool]) -> None:
+    tool_string = render_text_description_and_args(tools)
+    expected_string = """search: search(query: str) -> str - Lookup things online., \
+args: {'query': {'title': 'Query', 'type': 'string'}}
+calculator: calculator(expression: str) -> str - Do math., \
+args: {'expression': {'title': 'Expression', 'type': 'string'}}"""
+    assert tool_string == expected_string