`tool()`

Tool is a helper function that infers the tool paramaters for its execute method.

It does not have any runtime behavior, but it helps TypeScript infer the types of the parameters for the execute method.

Without this helper function, TypeScript is unable to connect the parameters property to the execute method, and the argument types of execute cannot be inferred.

import { tool } from 'ai';
import { z } from 'zod';

export const weatherTool = tool({
  description: 'Get the weather in a location',
  parameters: z.object({
    location: z.string().describe('The location to get the weather for'),
  }),
  // location below is inferred to be a string:
  execute: async ({ location }) => ({
    location,
    temperature: 72 + Math.floor(Math.random() * 21) - 10,
  }),
});

Import

import { tool } from "ai"

API Signature

tool:

CoreTool

The tool definition.

CoreTool

description?:

string

Information about the purpose of the tool including details on how and when it can be used by the model.

parameters:

zod schema

The schema of the input that the tool expects. The language model will use this to generate the input. It is also used to validate the output of the language model. Use descriptions to make the input understandable for the language model.

execute?:

async (parameters) => any

An async function that is called with the arguments from the tool call and produces a result. If not provided, the tool will not be executed automatically.

Returns

The tool that was passed in.