FrontierAI.Engineer
Agentic AI Foundations & Architectures

Tool-Calling Agent

A tool-calling agent is an AI agent that extends a language model's capabilities by invoking external functions — such as web search, code execution, or database queries — and incorporating the results into its reasoning. The model emits a structured tool-call request, a runtime executes the function, and the returned observation is appended to context before the model continues.

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