Function: defineTool()

function defineTool<TContext>(name, config): GroupedToolBuilder<TContext>;

Defined in: packages/core/src/core/builder/defineTool.ts:220

Define a tool using a high-level JSON-like config.

This is the recommended entry point for most developers. The framework handles all Zod schema creation, validation, and MCP protocol details internally.

Type Parameters

Type Parameter	Default type
TContext	void

Parameters

Parameter	Type
name	string
config	ToolConfig<TContext>

Returns

GroupedToolBuilder<TContext>

Example

const echo = defineTool('echo', {
    actions: {
        say: {
            params: { message: 'string' },
            handler: async (ctx, args) => success(args.message),
        },
    },
});

// Tool with shared params + groups + middleware
const platform = defineTool<AppContext>('platform', {
    description: 'Platform management',
    tags: ['admin'],
    shared: { workspace_id: { type: 'string', description: 'Workspace ID' } },
    middleware: [requireAuth],
    groups: {
        users: {
            description: 'User management',
            actions: {
                list: { readOnly: true, handler: listUsers },
                ban:  { destructive: true, params: { user_id: 'string' }, handler: banUser },
            },
        },
    },
});

// Register normally
const registry = new ToolRegistry<AppContext>();
registry.register(platform);

See

• createTool for the power-user builder API
• ToolRegistry.register for registration