Filesystem MCP Server

Instructions

Implementation Reference

• src/index.ts:317-339 (handler)

  The handler for the 'list_directory' tool. It validates the path, reads the directory contents, stats each entry to determine if it's a file or directory, formats with [DIR] or [FILE] prefixes, and returns the list as text.

  case 'list_directory': {
    const { path: dirPath } = request.params.arguments as { path: string };
    validatePath(dirPath);
    
    const entries = await fs.readdir(dirPath);
    const formattedEntries = await Promise.all(
      entries.map(async (entry) => {
        const entryPath = path.join(dirPath, entry);
        const stats = await fs.stat(entryPath);
        const prefix = stats.isDirectory() ? '[DIR]' : '[FILE]';
        return `${prefix} ${entry}`;
      })
    );
    
    return {
      content: [
        {
          type: 'text',
          text: formattedEntries.join('\n'),
        },
      ],
    };
  }

• src/index.ts:158-171 (registration)

  Registration of the 'list_directory' tool in the list of tools provided by ListToolsRequestSchema, including its name, description, and input schema.

  {
    name: 'list_directory',
    description: 'List directory contents with [FILE] or [DIR] prefixes',
    inputSchema: {
      type: 'object',
      properties: {
        path: {
          type: 'string',
          description: 'Path to the directory to list',
        },
      },
      required: ['path'],
    },
  },

• src/index.ts:161-170 (schema)

  The input schema definition for the 'list_directory' tool, specifying the required 'path' parameter.

  inputSchema: {
    type: 'object',
    properties: {
      path: {
        type: 'string',
        description: 'Path to the directory to list',
      },
    },
    required: ['path'],
  },