Agent Skills

Anthropic Tool Use API

The Anthropic Tool Use API allows AI agents built on Claude to call client-defined functions or Anthropic-provided server tools such as web search, code execution, and web fetch. Tools are declared in the API request and Claude decides when to invoke them based on context. Server tools run on Anthropic infrastructure while client tools execute in the calling application.

GitHub

Documentation

📖
Documentation
https://platform.claude.com/docs/en/docs/agents-and-tools/tool-use/overview
📖
APIReference
https://platform.claude.com/docs/en/docs/agents-and-tools/tool-use/tool-reference
📖
GettingStarted
https://platform.claude.com/docs/en/docs/agents-and-tools/tool-use/build-a-tool-using-agent

Other Resources

🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/agent-skills/refs/heads/main/apis.yml

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API entry from apis.yml

apis.yml Raw ↑ 
name: Anthropic Tool Use API
description: The Anthropic Tool Use API allows AI agents built on Claude to call client-defined functions
  or Anthropic-provided server tools such as web search, code execution, and web fetch. Tools are declared
  in the API request and Claude decides when to invoke them based on context. Server tools run on Anthropic
  infrastructure while client tools execute in the calling application.
humanURL: https://platform.claude.com/docs/en/docs/agents-and-tools/tool-use/overview
baseURL: https://api.anthropic.com
tags:
- Anthropic
- Tool Use
- Function Calling
- Claude
- AI Agents
properties:
- type: Documentation
  url: https://platform.claude.com/docs/en/docs/agents-and-tools/tool-use/overview
- type: APIReference
  url: https://platform.claude.com/docs/en/docs/agents-and-tools/tool-use/tool-reference
- type: GettingStarted
  url: https://platform.claude.com/docs/en/docs/agents-and-tools/tool-use/build-a-tool-using-agent