Tool Use
An agent's ability to call external tools: searches, databases, APIs, code execution.
Why it matters
Tool use separates agents from chatbots. With tools, AI takes action — not just generates text.
In practice
Claude Code has: Read, Write, Edit, Bash, Grep, Glob, and MCP tools. Each call shown for user approval.
Related terms
Function Calling (Tool Calling)
The model's ability to trigger external tools: searches, databases, APIs, code execution.
MCP (Model Context Protocol)
An open standard for connecting AI tools to external services. "USB-C for AI."
Agent (AI Agent)
An AI system that plans, decides, and acts autonomously toward goals, rather than simply responding to prompts.
Dynamic Tool Selection
An agent's ability to choose which tools to use based on the task at hand.