Agent concepts

Function calling

OpenAI's term for tool use. Same concept, slightly different format.

also known as: tool calling

In depth

Function calling is what OpenAI named the structured-output mechanism that lets an LLM invoke a function. Anthropic calls it tool use, Mistral calls it function calling, Gemini has its own convention. Functionally they are the same primitive. Most agent runtimes normalise across them so your YAML does not have to know the difference.

Related concepts

Tool useThe LLM capability to emit a structured call to an external function, which the runtime executes and feeds back as context.AI agentAn autonomous program that uses an LLM to plan and execute multi-step tasks via tools, in a loop, until a goal is reached.

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Engineering notes from the Digitorn team. No marketing, no launch announcements, no "10 prompts that will change your life". Just the things we write that we'd want to read.

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