withlove

What is Tool calling?

Updated May 2026

Tool calling (or function calling) is when an AI model decides to call a real piece of code instead of just generating text — like checking a calendar before suggesting times.

Tool calling is what turns a language model into an agent. Without tools, the model can only generate text. With tools, it can read your real data, take real actions, and verify facts before answering.

A typical tool-calling loop: the visitor asks 'when can we meet next week?' → the AI decides to call check_availability → the tool returns real freebusy → the AI proposes real slots from that data.

Frequently asked questions

Is tool calling the same as function calling?

Yes. The terms are interchangeable. OpenAI popularized 'function calling'; Anthropic uses 'tool use'. They describe the same pattern.

Related terms

Your own AI assistant in five minutes

Skip the jargon. withlove gives you a working AI agent at a shareable URL — voice, calendar, prices, leads — without any of the setup.

Try withlove free