@nestia/core/lib/decorators/McpRoute.d.ts

Super-fast validation decorators of NestJS

import { IRequestBodyValidator } from "../options/IRequestBodyValidator";
/**
 * MCP (Model Context Protocol) route decorator.
 *
 * `@McpRoute()` marks a controller method as a callable MCP tool. When the
 * application bootstraps, every method annotated with this decorator is
 * registered on the MCP server built by {@link McpAdaptor.upgrade}, making it
 * reachable by LLM clients through the standard Streamable HTTP transport.
 *
 * The public form takes only the tool's `name` (string). Human-readable
 * `description` and `title` are read from the method's JSDoc:
 *
 * - `description`: the JSDoc comment body.
 * - `title`: the value of an optional `@title` JSDoc tag.
 *
 * For type-safe tool inputs, decorate exactly one parameter of the method with
 * {@link McpRoute.Params}. The parameter type `T` is analyzed at compile time by
 * the nestia transformer, which generates both a runtime validator and the JSON
 * Schema attached to `inputSchema` in `tools/list` responses.
 *
 * For the MCP endpoint to actually be served, call {@link McpAdaptor.upgrade} on
 * the {@link INestApplication} instance at bootstrap. The decorator alone only
 * stores reflection metadata.
 *
 * @author wildduck - https://github.com/wildduck2
 * @example
 *   ```typescript
 *   import core from "@nestia/core";
 *
 *   @Controller()
 *   export class WeatherController {
 *     /**
 *      * Return current weather for a city.
 *      *
 *      * @title Get weather
 *      *\/
 *     @core.McpRoute("get_weather")
 *     public async get(
 *       @core.McpRoute.Params() params: { city: string },
 *     ): Promise<{ temp: number }> {
 *       return { temp: 22 };
 *     }
 *   }
 *   ```;
 *
 * @param name Unique tool identifier exposed to MCP clients via `tools/list`.
 * @returns Method decorator.
 */
export declare function McpRoute(name: string): MethodDecorator;
export declare namespace McpRoute {
    /**
     * Parameter decorator for an MCP tool's input arguments.
     *
     * `@McpRoute.Params<T>()` validates the `arguments` object from a
     * `tools/call` request against the TypeScript type `T` using typia. A failed
     * validation surfaces to the client as a JSON-RPC `-32602` (`InvalidParams`)
     * error with structured diagnostics, giving the LLM precise feedback to
     * self-correct.
     *
     * MCP tools accept exactly one arguments object; applying this decorator more
     * than once on a single method is a compile-time error. The decorated type
     * `T` must be an object type without dynamic properties.
     *
     * @author wildduck - https://github.com/wildduck2
     * @param validator Optional custom validator. Default is `typia.assert()`.
     * @returns Parameter decorator.
     */
    function Params<T>(validator?: IRequestBodyValidator<T>): ParameterDecorator;
}