Interface McpServerMcp

The public interface returned by create() in mcp.ts and stored in the MCP layer of the Node-in-Layers system context.

Typical usage:

const mcpServer = mcp.create(context)
mcpServer.addTool(myTool)
await mcpServer.start(systemContext)

interface McpServerMcp {
    addAdditionalRoute: (route: ExpressRoute) => void;
    addAnnotatedFunction: <
        TIn extends Readonly<{ [s: string]: JsonAble }>,
        TOut extends void | Readonly<{ [s: string]: JsonAble }>,
    >(
        annotatedFunction: NilAnnotatedFunction<TIn, TOut>,
        options?: { description?: string; name?: string },
    ) => void;
    addCrossLayerPropMiddleware: (middleware: CrossLayerPropMiddleware) => void;
    addPreRouteMiddleware: (middleware: ExpressMiddleware) => void;
    addTool: (tool: McpTool) => void;
    getApp: <
        T extends
            Readonly<
                {
                    "@node-in-layers/mcp-server": {
                        hiddenPaths?: string[];
                        hideComponents?: {
                            allModels?: boolean;
                            domains?: string[];
                            paths?: readonly string[];
                        };
                        logging?: {
                            requestLogGetData?: (req: Request) => Record<string, any>;
                            requestLogLevel?: LogLevelNames;
                            responseLogGetData?: (req: Request) => Record<string, any>;
                            responseLogLevel?: LogLevelNames;
                        };
                        server: {
                            connection: | Without<
                                Readonly<{ type: ... }>,
                                Readonly<
                                    {
                                        headers?: ...;
                                        retry?: ...;
                                        timeout?: ...;
                                        type: ...;
                                        url: ...;
                                    },
                                >,
                            > & Readonly<
                                {
                                    headers?: (...)
                                    | (...);
                                    retry?: (...) | (...);
                                    timeout?: (...) | (...);
                                    type: "http";
                                    url: string;
                                },
                            >
                            | Without<
                                Readonly<
                                    {
                                        headers?: ...;
                                        retry?: ...;
                                        timeout?: ...;
                                        type: ...;
                                        url: ...;
                                    },
                                >,
                                Readonly<{ type: ... }>,
                            > & Readonly<{ type: "cli" }>;
                        };
                        startHere?: {
                            description?: string;
                            examplesOfUse?: readonly Readonly<
                                {
                                    description?: ...;
                                    details?: ...;
                                    example?: ...;
                                    name: ...;
                                    tags?: ...;
                                    value?: ...;
                                },
                            >[];
                            hideDefaultSystemEntries?: boolean;
                            includeDomains?: boolean;
                            includeFeatures?: boolean;
                            name?: string;
                        };
                        stateful?: boolean;
                        systemDescription?: { description?: string; version?: string };
                        version?: string;
                    };
                },
            > & Readonly<
                {
                    "@node-in-layers/core": CoreConfig;
                    environment: string;
                    systemName: string;
                },
            >,
    >(
        systemContext: any,
        options?: Readonly<
            { jsonBodyParser?: { limit?: string; strict?: boolean } },
        >,
    ) => Promise<Express>;
    set: (key: string, value: any) => void;
    start: <
        T extends
            Readonly<
                {
                    "@node-in-layers/mcp-server": {
                        hiddenPaths?: string[];
                        hideComponents?: {
                            allModels?: boolean;
                            domains?: string[];
                            paths?: readonly string[];
                        };
                        logging?: {
                            requestLogGetData?: (req: Request) => Record<string, any>;
                            requestLogLevel?: LogLevelNames;
                            responseLogGetData?: (req: Request) => Record<string, any>;
                            responseLogLevel?: LogLevelNames;
                        };
                        server: {
                            connection: | Without<
                                Readonly<{ type: ... }>,
                                Readonly<
                                    {
                                        headers?: ...;
                                        retry?: ...;
                                        timeout?: ...;
                                        type: ...;
                                        url: ...;
                                    },
                                >,
                            > & Readonly<
                                {
                                    headers?: (...)
                                    | (...);
                                    retry?: (...) | (...);
                                    timeout?: (...) | (...);
                                    type: "http";
                                    url: string;
                                },
                            >
                            | Without<
                                Readonly<
                                    {
                                        headers?: ...;
                                        retry?: ...;
                                        timeout?: ...;
                                        type: ...;
                                        url: ...;
                                    },
                                >,
                                Readonly<{ type: ... }>,
                            > & Readonly<{ type: "cli" }>;
                        };
                        startHere?: {
                            description?: string;
                            examplesOfUse?: readonly Readonly<
                                {
                                    description?: ...;
                                    details?: ...;
                                    example?: ...;
                                    name: ...;
                                    tags?: ...;
                                    value?: ...;
                                },
                            >[];
                            hideDefaultSystemEntries?: boolean;
                            includeDomains?: boolean;
                            includeFeatures?: boolean;
                            name?: string;
                        };
                        stateful?: boolean;
                        systemDescription?: { description?: string; version?: string };
                        version?: string;
                    };
                },
            > & Readonly<
                {
                    "@node-in-layers/core": CoreConfig;
                    environment: string;
                    systemName: string;
                },
            >,
    >(
        systemContext: any,
        options?: Readonly<
            { jsonBodyParser?: { limit?: string; strict?: boolean } },
        >,
    ) => Promise<void>;
}

Index

Properties

addAdditionalRoute addAnnotatedFunction addCrossLayerPropMiddleware addPreRouteMiddleware addTool getApp set start

Properties

`Readonly`addAdditionalRoute

addAdditionalRoute: (route: ExpressRoute) => void

Registers an additional Express route alongside the MCP endpoint. Must be called before start() or getApp().

Type Declaration

- (route: ExpressRoute): void
- Parameters
  - route: ExpressRoute
    An ExpressRoute definition.
  Returns void

`Readonly`addAnnotatedFunction

addAnnotatedFunction: <
    TIn extends Readonly<{ [s: string]: JsonAble }>,
    TOut extends void | Readonly<{ [s: string]: JsonAble }>,
>(
    annotatedFunction: NilAnnotatedFunction<TIn, TOut>,
    options?: { description?: string; name?: string },
) => void

Adds an annotated function as a tool.

Type Declaration

- <
      TIn extends Readonly<{ [s: string]: JsonAble }>,
      TOut extends void | Readonly<{ [s: string]: JsonAble }>,
  >(
      annotatedFunction: NilAnnotatedFunction<TIn, TOut>,
      options?: { description?: string; name?: string },
  ): void
- Type Parameters
  - TIn extends Readonly<{ [s: string]: JsonAble }>
  - TOut extends void | Readonly<{ [s: string]: JsonAble }>
  Parameters
  - annotatedFunction: NilAnnotatedFunction<TIn, TOut>
    The annotated function to add as a tool.
  - Optionaloptions: { description?: string; name?: string }
    - Optionaldescription?: string
      A replacement description for the function.
    - Optionalname?: string
      A replacement name for the function.
  Returns void
  void

`Readonly`addCrossLayerPropMiddleware

addCrossLayerPropMiddleware: (middleware: CrossLayerPropMiddleware) => void

Adds a middleware function that will be called before the MCP route, that can extract information that will be placed into the cross layer props.

NOTE: If you return "logging" cross layer props, it will be merged in appropriately with the normal cross layer props. This can be useful for adding additional IDS.

Having said that, NON-"logging" properties, are merged together, and can result in overriding values.

Type Declaration

- (middleware: CrossLayerPropMiddleware): void
- Parameters
  - middleware: CrossLayerPropMiddleware
  Returns void

`Readonly`addPreRouteMiddleware

addPreRouteMiddleware: (middleware: ExpressMiddleware) => void

Registers an Express middleware to run before the MCP route handler. Useful for auth, logging, or rate-limiting. Must be called before start() or getApp().

Type Declaration

- (middleware: ExpressMiddleware): void
- Parameters
  - middleware: ExpressMiddleware
    An ExpressMiddleware function.
  Returns void

`Readonly`addTool

addTool: (tool: McpTool) => void

Registers a custom McpTool with the server. Call this before start() or getApp().

Type Declaration

- (tool: McpTool): void
- Parameters
  - tool: McpTool
    The tool definition to register.
  Returns void

`Readonly`getApp

getApp: <
    T extends
        Readonly<
            {
                "@node-in-layers/mcp-server": {
                    hiddenPaths?: string[];
                    hideComponents?: {
                        allModels?: boolean;
                        domains?: string[];
                        paths?: readonly string[];
                    };
                    logging?: {
                        requestLogGetData?: (req: Request) => Record<string, any>;
                        requestLogLevel?: LogLevelNames;
                        responseLogGetData?: (req: Request) => Record<string, any>;
                        responseLogLevel?: LogLevelNames;
                    };
                    server: {
                        connection: | Without<
                            Readonly<{ type: ... }>,
                            Readonly<
                                {
                                    headers?: ...;
                                    retry?: ...;
                                    timeout?: ...;
                                    type: ...;
                                    url: ...;
                                },
                            >,
                        > & Readonly<
                            {
                                headers?: (...)
                                | (...);
                                retry?: (...) | (...);
                                timeout?: (...) | (...);
                                type: "http";
                                url: string;
                            },
                        >
                        | Without<
                            Readonly<
                                {
                                    headers?: ...;
                                    retry?: ...;
                                    timeout?: ...;
                                    type: ...;
                                    url: ...;
                                },
                            >,
                            Readonly<{ type: ... }>,
                        > & Readonly<{ type: "cli" }>;
                    };
                    startHere?: {
                        description?: string;
                        examplesOfUse?: readonly Readonly<
                            {
                                description?: ...;
                                details?: ...;
                                example?: ...;
                                name: ...;
                                tags?: ...;
                                value?: ...;
                            },
                        >[];
                        hideDefaultSystemEntries?: boolean;
                        includeDomains?: boolean;
                        includeFeatures?: boolean;
                        name?: string;
                    };
                    stateful?: boolean;
                    systemDescription?: { description?: string; version?: string };
                    version?: string;
                };
            },
        > & Readonly<
            {
                "@node-in-layers/core": CoreConfig;
                environment: string;
                systemName: string;
            },
        >,
>(
    systemContext: any,
    options?: Readonly<
        { jsonBodyParser?: { limit?: string; strict?: boolean } },
    >,
) => Promise<Express>

Builds and returns the configured Express app without starting the HTTP listener. Useful when you want to integrate the MCP server into an existing Express application or test the app directly.

Throws if the connection type is not 'http'.

Type Declaration

- <
      T extends
          Readonly<
              {
                  "@node-in-layers/mcp-server": {
                      hiddenPaths?: string[];
                      hideComponents?: {
                          allModels?: boolean;
                          domains?: string[];
                          paths?: readonly string[];
                      };
                      logging?: {
                          requestLogGetData?: (req: Request) => Record<string, any>;
                          requestLogLevel?: LogLevelNames;
                          responseLogGetData?: (req: Request) => Record<string, any>;
                          responseLogLevel?: LogLevelNames;
                      };
                      server: {
                          connection: | Without<
                              Readonly<{ type: ... }>,
                              Readonly<
                                  {
                                      headers?: ...;
                                      retry?: ...;
                                      timeout?: ...;
                                      type: ...;
                                      url: ...;
                                  },
                              >,
                          > & Readonly<
                              {
                                  headers?: (...)
                                  | (...);
                                  retry?: (...) | (...);
                                  timeout?: (...) | (...);
                                  type: "http";
                                  url: string;
                              },
                          >
                          | Without<
                              Readonly<
                                  {
                                      headers?: ...;
                                      retry?: ...;
                                      timeout?: ...;
                                      type: ...;
                                      url: ...;
                                  },
                              >,
                              Readonly<{ type: ... }>,
                          > & Readonly<{ type: "cli" }>;
                      };
                      startHere?: {
                          description?: string;
                          examplesOfUse?: readonly Readonly<
                              {
                                  description?: ...;
                                  details?: ...;
                                  example?: ...;
                                  name: ...;
                                  tags?: ...;
                                  value?: ...;
                              },
                          >[];
                          hideDefaultSystemEntries?: boolean;
                          includeDomains?: boolean;
                          includeFeatures?: boolean;
                          name?: string;
                      };
                      stateful?: boolean;
                      systemDescription?: { description?: string; version?: string };
                      version?: string;
                  };
              },
          > & Readonly<
              {
                  "@node-in-layers/core": CoreConfig;
                  environment: string;
                  systemName: string;
              },
          >,
  >(
      systemContext: any,
      options?: Readonly<
          { jsonBodyParser?: { limit?: string; strict?: boolean } },
      >,
  ): Promise<Express>
- Type Parameters
  - T extends Readonly<
        {
            "@node-in-layers/mcp-server": {
                hiddenPaths?: string[];
                hideComponents?: {
                    allModels?: boolean;
                    domains?: string[];
                    paths?: readonly string[];
                };
                logging?: {
                    requestLogGetData?: (req: Request) => Record<string, any>;
                    requestLogLevel?: LogLevelNames;
                    responseLogGetData?: (req: Request) => Record<string, any>;
                    responseLogLevel?: LogLevelNames;
                };
                server: {
                    connection: | Without<
                        Readonly<{ type: ... }>,
                        Readonly<
                            { headers?: ...; retry?: ...; timeout?: ...; type: ...; url: ... },
                        >,
                    > & Readonly<
                        {
                            headers?: (...)
                            | (...);
                            retry?: (...) | (...);
                            timeout?: (...) | (...);
                            type: "http";
                            url: string;
                        },
                    >
                    | Without<
                        Readonly<
                            { headers?: ...; retry?: ...; timeout?: ...; type: ...; url: ... },
                        >,
                        Readonly<{ type: ... }>,
                    > & Readonly<{ type: "cli" }>;
                };
                startHere?: {
                    description?: string;
                    examplesOfUse?: readonly Readonly<
                        {
                            description?: ...;
                            details?: ...;
                            example?: ...;
                            name: ...;
                            tags?: ...;
                            value?: ...;
                        },
                    >[];
                    hideDefaultSystemEntries?: boolean;
                    includeDomains?: boolean;
                    includeFeatures?: boolean;
                    name?: string;
                };
                stateful?: boolean;
                systemDescription?: { description?: string; version?: string };
                version?: string;
            };
        },
    > & Readonly<
        {
            "@node-in-layers/core": CoreConfig;
            environment: string;
            systemName: string;
        },
    >
  Parameters
  - systemContext: any
    The fully-initialised Node-in-Layers system context.
  - Optionaloptions: Readonly<{ jsonBodyParser?: { limit?: string; strict?: boolean } }>
    Optional Express body-parser settings.
  Returns Promise<Express>

`Readonly`set

set: (key: string, value: any) => void

Calls app.set(key, value) on the underlying Express app. Must be called before start() or getApp().

Type Declaration

- (key: string, value: any): void
- Parameters
  - key: string
    Express setting name (e.g. 'trust proxy').
  - value: any
    Value to assign.
  Returns void

`Readonly`start

start: <
    T extends
        Readonly<
            {
                "@node-in-layers/mcp-server": {
                    hiddenPaths?: string[];
                    hideComponents?: {
                        allModels?: boolean;
                        domains?: string[];
                        paths?: readonly string[];
                    };
                    logging?: {
                        requestLogGetData?: (req: Request) => Record<string, any>;
                        requestLogLevel?: LogLevelNames;
                        responseLogGetData?: (req: Request) => Record<string, any>;
                        responseLogLevel?: LogLevelNames;
                    };
                    server: {
                        connection: | Without<
                            Readonly<{ type: ... }>,
                            Readonly<
                                {
                                    headers?: ...;
                                    retry?: ...;
                                    timeout?: ...;
                                    type: ...;
                                    url: ...;
                                },
                            >,
                        > & Readonly<
                            {
                                headers?: (...)
                                | (...);
                                retry?: (...) | (...);
                                timeout?: (...) | (...);
                                type: "http";
                                url: string;
                            },
                        >
                        | Without<
                            Readonly<
                                {
                                    headers?: ...;
                                    retry?: ...;
                                    timeout?: ...;
                                    type: ...;
                                    url: ...;
                                },
                            >,
                            Readonly<{ type: ... }>,
                        > & Readonly<{ type: "cli" }>;
                    };
                    startHere?: {
                        description?: string;
                        examplesOfUse?: readonly Readonly<
                            {
                                description?: ...;
                                details?: ...;
                                example?: ...;
                                name: ...;
                                tags?: ...;
                                value?: ...;
                            },
                        >[];
                        hideDefaultSystemEntries?: boolean;
                        includeDomains?: boolean;
                        includeFeatures?: boolean;
                        name?: string;
                    };
                    stateful?: boolean;
                    systemDescription?: { description?: string; version?: string };
                    version?: string;
                };
            },
        > & Readonly<
            {
                "@node-in-layers/core": CoreConfig;
                environment: string;
                systemName: string;
            },
        >,
>(
    systemContext: any,
    options?: Readonly<
        { jsonBodyParser?: { limit?: string; strict?: boolean } },
    >,
) => Promise<void>

Starts the MCP server. For HTTP connections, binds an Express app to the configured port. For CLI connections, connects the stdio transport.

Type Declaration

- <
      T extends
          Readonly<
              {
                  "@node-in-layers/mcp-server": {
                      hiddenPaths?: string[];
                      hideComponents?: {
                          allModels?: boolean;
                          domains?: string[];
                          paths?: readonly string[];
                      };
                      logging?: {
                          requestLogGetData?: (req: Request) => Record<string, any>;
                          requestLogLevel?: LogLevelNames;
                          responseLogGetData?: (req: Request) => Record<string, any>;
                          responseLogLevel?: LogLevelNames;
                      };
                      server: {
                          connection: | Without<
                              Readonly<{ type: ... }>,
                              Readonly<
                                  {
                                      headers?: ...;
                                      retry?: ...;
                                      timeout?: ...;
                                      type: ...;
                                      url: ...;
                                  },
                              >,
                          > & Readonly<
                              {
                                  headers?: (...)
                                  | (...);
                                  retry?: (...) | (...);
                                  timeout?: (...) | (...);
                                  type: "http";
                                  url: string;
                              },
                          >
                          | Without<
                              Readonly<
                                  {
                                      headers?: ...;
                                      retry?: ...;
                                      timeout?: ...;
                                      type: ...;
                                      url: ...;
                                  },
                              >,
                              Readonly<{ type: ... }>,
                          > & Readonly<{ type: "cli" }>;
                      };
                      startHere?: {
                          description?: string;
                          examplesOfUse?: readonly Readonly<
                              {
                                  description?: ...;
                                  details?: ...;
                                  example?: ...;
                                  name: ...;
                                  tags?: ...;
                                  value?: ...;
                              },
                          >[];
                          hideDefaultSystemEntries?: boolean;
                          includeDomains?: boolean;
                          includeFeatures?: boolean;
                          name?: string;
                      };
                      stateful?: boolean;
                      systemDescription?: { description?: string; version?: string };
                      version?: string;
                  };
              },
          > & Readonly<
              {
                  "@node-in-layers/core": CoreConfig;
                  environment: string;
                  systemName: string;
              },
          >,
  >(
      systemContext: any,
      options?: Readonly<
          { jsonBodyParser?: { limit?: string; strict?: boolean } },
      >,
  ): Promise<void>
- Type Parameters
  - T extends Readonly<
        {
            "@node-in-layers/mcp-server": {
                hiddenPaths?: string[];
                hideComponents?: {
                    allModels?: boolean;
                    domains?: string[];
                    paths?: readonly string[];
                };
                logging?: {
                    requestLogGetData?: (req: Request) => Record<string, any>;
                    requestLogLevel?: LogLevelNames;
                    responseLogGetData?: (req: Request) => Record<string, any>;
                    responseLogLevel?: LogLevelNames;
                };
                server: {
                    connection: | Without<
                        Readonly<{ type: ... }>,
                        Readonly<
                            { headers?: ...; retry?: ...; timeout?: ...; type: ...; url: ... },
                        >,
                    > & Readonly<
                        {
                            headers?: (...)
                            | (...);
                            retry?: (...) | (...);
                            timeout?: (...) | (...);
                            type: "http";
                            url: string;
                        },
                    >
                    | Without<
                        Readonly<
                            { headers?: ...; retry?: ...; timeout?: ...; type: ...; url: ... },
                        >,
                        Readonly<{ type: ... }>,
                    > & Readonly<{ type: "cli" }>;
                };
                startHere?: {
                    description?: string;
                    examplesOfUse?: readonly Readonly<
                        {
                            description?: ...;
                            details?: ...;
                            example?: ...;
                            name: ...;
                            tags?: ...;
                            value?: ...;
                        },
                    >[];
                    hideDefaultSystemEntries?: boolean;
                    includeDomains?: boolean;
                    includeFeatures?: boolean;
                    name?: string;
                };
                stateful?: boolean;
                systemDescription?: { description?: string; version?: string };
                version?: string;
            };
        },
    > & Readonly<
        {
            "@node-in-layers/core": CoreConfig;
            environment: string;
            systemName: string;
        },
    >
  Parameters
  - systemContext: any
    The fully-initialised Node-in-Layers system context, used to resolve features and models at runtime.
  - Optionaloptions: Readonly<{ jsonBodyParser?: { limit?: string; strict?: boolean } }>
    Optional Express body-parser settings.
  Returns Promise<void>

Interface McpServerMcp

Index

Properties

Properties

ReadonlyaddAdditionalRoute

Type Declaration

Parameters

Returns void

ReadonlyaddAnnotatedFunction

Type Declaration

Type Parameters

Parameters

Optionaldescription?: string

Optionalname?: string

Returns void

ReadonlyaddCrossLayerPropMiddleware

Type Declaration

Parameters

Returns void

ReadonlyaddPreRouteMiddleware

Type Declaration

Parameters

Returns void

ReadonlyaddTool

Type Declaration

Parameters

Returns void

ReadonlygetApp

Type Declaration

Type Parameters

Parameters

Returns Promise<Express>

Readonlyset

Type Declaration

Parameters

Returns void

Readonlystart

Type Declaration

Type Parameters

Parameters

Returns Promise<void>

Settings

On This Page

`Readonly`addAdditionalRoute

`Readonly`addAnnotatedFunction

`Optional`description?: string

`Optional`name?: string

`Readonly`addCrossLayerPropMiddleware

`Readonly`addPreRouteMiddleware

`Readonly`addTool

`Readonly`getApp

`Readonly`set

`Readonly`start