Modes MCP Server

Instructions

Implementation Reference

• src/index.ts:331-341 (handler)

  Handler for the 'list_modes' tool that reads the configuration file using readConfig() and returns the customModes array as formatted JSON text in the MCP response.

  case 'list_modes': {
    const config = await this.readConfig();
    return {
      content: [
        {
          type: 'text',
          text: JSON.stringify(config.customModes, null, 2),
        },
      ],
    };
  }

• src/index.ts:176-183 (registration)

  Registration of the 'list_modes' tool in the ListTools response, including its name, description, and empty input schema.

  {
    name: 'list_modes',
    description: 'List all custom modes',
    inputSchema: {
      type: 'object',
      properties: {},
    },
  },

• src/index.ts:61-64 (schema)

  Zod schema for the modes configuration file structure, which defines the format of data returned by list_modes (array of custom modes).

  const CustomModesConfigSchema = z.object({
    customModes: z.array(CustomModeSchema),
  });

• src/index.ts:132-148 (helper)

  Helper function to read, parse, and validate the modes configuration file, directly used by the list_modes handler.

  private async readConfig() {
    try {
      // Create default config if file doesn't exist
      if (!fs.existsSync(this.configPath)) {
        await fs.writeFile(this.configPath, JSON.stringify({ customModes: [] }, null, 2), 'utf-8');
      }
  
      const content = await fs.readFile(this.configPath, 'utf-8');
      const config = JSON.parse(content);
      return CustomModesConfigSchema.parse(config);
    } catch (error) {
      throw new McpError(
        ErrorCode.InternalError,
        `Failed to read config: ${error instanceof Error ? error.message : String(error)}`
      );
    }
  }