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更新日: 2026-06-06

Overview

Function Calling allows models to call functions you define, enabling interaction with external systems. The model does not execute functions directly — it returns the function name and arguments, and your code executes them and returns the results to the model.

Complete Example

Force a Specific Function Call

Supported Models

For the OpenAI-compatible Function Calling examples in this page, use the following verified baseline first:
  • gpt-5.5
Tool calling with gpt-5.5 was verified in Crazyrouter production on March 23, 2026. For other vendors, check their dedicated pages first because request formats and support details can differ.