Tool Calling with LangChain

Large Language Models (LLMs) can interact with external data sources via tool calling functionality. Tool calling is a powerful technique that allows developers to build sophisticated applications that can leverage LLMs to access, interact and manipulate external resources like databases, files and APIs.

Providers have been introducing native tool calling capability into their models. What this looks like in practice is that when the LLM provides an auto-completion to a prompt, it can return a list of tool invocations in addition to plain text. OpenAI was the first to release this roughly a year ago with “function calling”, which quickly evolved to “tool calling” in November. Since then, other model providers have followed: Gemini (in December), Mistral (in February), Fireworks (in March), Together (in March), Groq (in April), Cohere (in April) and Anthropic (in April).

All of these providers exposed slightly different interfaces (in particular: OpenAI, Anthropic, and Gemini, the three highest performing models, have very different interfaces). We’ve heard from the community a desire for a standardized interface for tool calling to make it easy to switch between these providers, which we’re excited to release today.

Blog: blog.langchain.dev/tool-calling-with-langchain/

Python:

List of chat models that shows status of tool calling capability: https://python.langchain.com/docs/int...
Tool calling explains the new tool calling interface: https://python.langchain.com/docs/mod...
Tool calling agent shows how to create an agent that uses the standardized tool calling interface: https://python.langchain.com/docs/mod...
LangGraph notebook shows how to create a LangGraph agent that uses the standardized tool calling interface: https://github.com/langchain-ai/langc...

JS:

List of chat models that shows status of tool calling capability: https://js.langchain.com/docs/integra...
Tool calling explains the new tool calling interface: https://python.langchain.com/docs/mod...
Tool calling agent shows how to create an agent that uses the standardized tool calling interface: https://js.langchain.com/docs/modules...