AI Glossarytechniques

Function Calling (Tool Use)

An AI capability where the model can decide to invoke external functions or APIs based on the conversation context.

How It Works

Function calling lets AI models take actions, not just generate text. You define available functions with their parameters, and the model decides when to call them. Example: a travel assistant with functions like searchFlights(origin, destination, date) and bookHotel(city, checkin, checkout). The model parses user intent, selects the right function, and extracts parameters. OpenAI, Anthropic, and Google all support this. It's the foundation of AI agents.

Common Use Cases

  • 1AI agents that take actions
  • 2Database queries from natural language
  • 3API orchestration
  • 4Multi-step workflows

Related Terms

Prompt Engineering

The practice of crafting effective instructions for AI models to produce desired outputs consistently.

AI Agent

An AI system that can autonomously plan, reason, use tools, and take actions to accomplish goals with minimal human intervention.

MCP (Model Context Protocol)

An open standard by Anthropic that provides a universal way for AI models to connect to external data sources and tools.

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