Agentic AI Glossary

Tool call

Structured model output that names a tool and supplies the arguments for running it.

Illustrative conversation

  1. The model requested delete_file. Is the file already gone?
  2. Not necessarily. The tool call is a request; the harness must still authorize and execute it.

Definition

A tool call is the structured request that identifies a tool and provides its arguments. It is not the same as execution: the host or harness still has to validate the request, apply authorization rules, run or deny it, and return a result to the model. That separation is especially important for destructive or externally visible actions.

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