Tool Use

Learn how Claude uses tool descriptions, input schemas, and tool_choice to decide when and which tool to call in your applications.

Learn to define tool schemas with name, description, and JSON input schema, then send messages with tools using the Anthropic Python SDK.

Learn to define tool schemas for Claude with name, description, and input_schema. Ensure correct tool calls and argument filling.

Learn to handle Claude's tool_use requests by executing tools, appending assistant responses, and returning tool_result blocks for robust tool-use.

Understand the four tool_choice modes and their modifier to control Claude's tool use. Learn when to use each setting with Python snippets.

Learn to build a multi-turn tool use loop in Python. Understand how to manage stateless API calls, execute tools, and handle tool_use and tool_result exchanges until Claude

Configure the Tool Search Tool with this cheatsheet. Learn about defer_loading and choose between regex and BM25 search variants.

Learn best practices for tool use with the Anthropic Python SDK, covering schema design, error handling, and multi-turn tool loops.

A single-page roundup of every highlight bullet from the 11 pages in the Tool Use section, grouped by source page so you can scan all 63 takeaways without opening each article individually.