Function calling gives a model access to defined operations with specified inputs and outputs. The model determines when to invoke a function, supplies the arguments, and incorporates the result into its response.
It is the mechanism underlying tool use and agentic workflows.
Alternative Names:
Tool Calling, Function Invocation
Why it Matters?
This capability is what lets a legal AI system look something up rather than recall it, which is the difference between retrieving a real document and generating a plausible one. It also creates a control point, since the available functions define what the system can actually do. Restricting functions to read operations, or requiring approval before any action with external effect, is a practical safeguard in litigation contexts.
Frequently Confused with
Related terms
Frequently asked questions
What does function calling enable?
Why is the function set a control point?
