claude-task-master/.cursor/rules/mcp.mdc

---
description: Guidelines for implementing and interacting with the Task Master MCP Server
globs: mcp-server/src/**/*, scripts/modules/**/*
alwaysApply: false
---

# Task Master MCP Server Guidelines

This document outlines the architecture and implementation patterns for the Task Master Model Context Protocol (MCP) server, designed for integration with tools like Cursor.

## Architecture Overview (See also: [`architecture.mdc`](mdc:.cursor/rules/architecture.mdc))

The MCP server acts as a bridge between external tools (like Cursor) and the core Task Master CLI logic. It leverages FastMCP for the server framework.

- **Flow**: `External Tool (Cursor)` <-> `FastMCP Server` <-> `MCP Tools` (`mcp-server/src/tools/*.js`) <-> `Core Logic Wrappers` (`mcp-server/src/core/task-master-core.js`) <-> `Core Modules` (`scripts/modules/*.js`)
- **Goal**: Provide a performant and reliable way for external tools to interact with Task Master functionality without directly invoking the CLI for every operation.

## Key Principles

- **Prefer Direct Function Calls**: For optimal performance and error handling, MCP tools should utilize direct function wrappers defined in [`task-master-core.js`](mdc:mcp-server/src/core/task-master-core.js). These wrappers call the underlying logic from the core modules (e.g., [`task-manager.js`](mdc:scripts/modules/task-manager.js)).
- **Use `executeMCPToolAction`**: This utility function in [`tools/utils.js`](mdc:mcp-server/src/tools/utils.js) is the standard wrapper for executing the main logic within an MCP tool's `execute` function. It handles common boilerplate like logging, argument processing, calling the core action (`*Direct` function), and formatting the response.
- **CLI Execution as Fallback**: The `executeTaskMasterCommand` utility in [`tools/utils.js`](mdc:mcp-server/src/tools/utils.js) allows executing commands via the CLI (`task-master ...`). This should **only** be used as a fallback if a direct function wrapper is not yet implemented or if a specific command intrinsically requires CLI execution.
- **Centralized Utilities** (See also: [`utilities.mdc`](mdc:.cursor/rules/utilities.mdc)):
    - Use `findTasksJsonPath` (in [`task-master-core.js`](mdc:mcp-server/src/core/task-master-core.js)) within direct function wrappers to locate the `tasks.json` file consistently.
    - **Leverage MCP Utilities**: The file [`tools/utils.js`](mdc:mcp-server/src/tools/utils.js) contains essential helpers for MCP tool implementation:
        - `getProjectRoot`: Normalizes project paths (used internally by other utils).
        - `handleApiResult`: Standardizes handling results from direct function calls (success/error).
        - `createContentResponse`/`createErrorResponse`: Formats successful/error MCP responses.
        - `processMCPResponseData`: Filters/cleans data for MCP responses (e.g., removing `details`, `testStrategy`). This is the default processor used by `executeMCPToolAction`.
        - `executeMCPToolAction`: The primary wrapper function for tool execution logic.
        - `executeTaskMasterCommand`: Fallback for executing CLI commands.

## Implementing MCP Support for a Command

Follow these steps to add MCP support for an existing Task Master command (see [`new_features.mdc`](mdc:.cursor/rules/new_features.mdc) for more detail):

1.  **Ensure Core Logic Exists**: Verify the core functionality is implemented and exported from the relevant module in `scripts/modules/`.
2.  **Create Direct Wrapper**: In [`task-master-core.js`](mdc:mcp-server/src/core/task-master-core.js):
    - Import the core function.
    - Create an `async function yourCommandDirect(args, log)` wrapper.
    - Inside the wrapper:
        - Use `findTasksJsonPath(args, log)` if the command needs the tasks file path.
        - Extract and validate arguments from `args`.
        - Call the imported core logic function.
        - Handle errors using `try/catch`.
        - Return a standardized object: `{ success: true, data: result }` or `{ success: false, error: { code: '...', message: '...' } }`.
    - Export the wrapper function and add it to the `directFunctions` map.
3.  **Create MCP Tool**: In `mcp-server/src/tools/`:
    - Create a new file (e.g., `yourCommand.js`).
    - Import `z` for parameter schema definition.
    - Import `executeMCPToolAction` from [`./utils.js`](mdc:mcp-server/src/tools/utils.js).
    - Import the `yourCommandDirect` wrapper function from `../core/task-master-core.js`.
    - Implement `registerYourCommandTool(server)`:
        - Call `server.addTool`.
        - Define `name`, `description`, and `parameters` using `zod`. Include `projectRoot` and `file` as optional parameters if relevant.
        - Define the `async execute(args, log)` function.
        - Inside `execute`, call `executeMCPToolAction`:
          ```javascript
          return executeMCPToolAction({
            actionFn: yourCommandDirect, // The direct function wrapper
            args,                     // Arguments from the tool call
            log,                      // MCP logger instance
            actionName: 'Your Command Description', // For logging
            // processResult: customProcessor // Optional: if default filtering isn't enough
          });
          ```
4.  **Register Tool**: Import and call `registerYourCommandTool` in [`mcp-server/src/tools/index.js`](mdc:mcp-server/src/tools/index.js).
5.  **Update `mcp.json`**: Add the new tool definition to the `tools` array in `.cursor/mcp.json`.

## Handling Responses

- MCP tools should return data formatted by `createContentResponse` (which stringifies objects) or `createErrorResponse`.
- The `processMCPResponseData` utility automatically removes potentially large fields like `details` and `testStrategy` from task objects before they are returned. This is the default behavior when using `executeMCPToolAction`. If specific fields need to be preserved or different fields removed, a custom `processResult` function can be passed to `executeMCPToolAction`.