[Tool binding](https://js.langchain.com/docs/concepts/tool_calling/#tool-binding): LLM should read this page when (needing to understand how tool calling works in LangChain, implementing LLM-powered function execution, or developing applications that require structured outputs from models) (This page explains tool calling in LangChain, covering the four key concepts: tool creation using the tool() function, tool binding to models via bindTools(), tool calling where models decide when to use tools and return structured arguments, and tool execution using the Runnable interface. It includes code examples, best practices, and diagrams illustrating the process flow.)

