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Function: tool()

tool<TSchema, TFn>(name, description, inputSchema, fn, options?): ZodToolDefinition<TSchema, Awaited<ReturnType<TFn>>>

Defined in: packages/core/src/utils/tools.ts:471

Simpler API for defining Zod tools with full type inference

Automatically infers:

  • Parameter types from Zod schema
  • Return type from function implementation

Type Parameters​

TSchema​

TSchema extends ZodType<unknown, unknown, $ZodTypeInternals<unknown, unknown>>

TFn​

TFn extends (params, options?) => unknown

Parameters​

name​

string

description​

string

inputSchema​

TSchema

fn​

TFn

options?​

requiresApproval?​

boolean | ((params) => boolean | Promise<boolean>)

strict?​

boolean

toModelOutput?​

(context) => ToolModelOutput

Returns​

ZodToolDefinition<TSchema, Awaited<ReturnType<TFn>>>

Examples​

const add = tool(
  'add',
  'Adds two numbers',
  z.object({
    a: z.number().describe('First number'),
    b: z.number().describe('Second number'),
  }),
  (params) => params.a + params.b  // params is { a: number, b: number }
);
// Tool return type is automatically inferred as number
const riskyTool = tool(
  'delete',
  'Delete something',
  z.object({ id: z.string() }),
  async ({ id }) => ({ deleted: true }),
  { requiresApproval: true, strict: true }
);