MCP Rand

Instructions

Implementation Reference

• src/handlers/generate-password.handler.ts:64-80 (handler)

  The handler function for the 'generate_password' tool. It extracts the optional length parameter, calls generateStrongPassword, and returns the generated password as tool result content.

  export const generatePasswordHandler = async (
    request: CallToolRequest
  ): Promise<CallToolResult> => {
    const args = request.params.arguments as { length?: number };
    const length = args.length ?? DEFAULT_LENGTH;
    
    const password = generateStrongPassword(length);
    
    return {
      content: [
        {
          type: 'text',
          text: password
        }
      ]
    };
  };

• src/handlers/generate-password.handler.ts:16-28 (schema)

  The tool specification (schema) defining the name, description, and input schema for the 'generate_password' tool.

  export const toolSpec = {
    name: 'generate_password',
    description: 'Generate a strong password with a mix of character types. WARNING: While this password is generated locally on your machine, it is recommended to use a dedicated password manager for generating and storing passwords securely.',
    inputSchema: {
      type: 'object' as const,
      properties: {
        length: {
          type: 'number',
          description: `Password length (minimum ${MIN_LENGTH}, default ${DEFAULT_LENGTH})`,
        }
      }
    }
  };

• src/index.ts:23-23 (registration)

  Registers the 'generate_password' tool handler in the MCP server registry under the 'tools/call' method.

  registry.register('tools/call', 'generate_password', generatePasswordHandler as Handler);

• src/handlers/generate-password.handler.ts:39-62 (helper)

  Core helper function that implements the password generation logic, ensuring diversity and minimum length.

  function generateStrongPassword(length: number): string {
    if (length < MIN_LENGTH) {
      throw new McpError(
        ErrorCode.InvalidParams,
        `Password length must be at least ${MIN_LENGTH} characters`
      );
    }
  
    // Ensure at least one character from each set
    let password = '';
    password += charsets.uppercase[Math.floor(Math.random() * charsets.uppercase.length)];
    password += charsets.lowercase[Math.floor(Math.random() * charsets.lowercase.length)];
    password += charsets.numbers[Math.floor(Math.random() * charsets.numbers.length)];
    password += charsets.special[Math.floor(Math.random() * charsets.special.length)];
  
    // Fill the rest with random characters from all sets
    const allChars = Object.values(charsets).join('');
    while (password.length < length) {
      password += allChars[Math.floor(Math.random() * allChars.length)];
    }
  
    // Shuffle to avoid predictable pattern of character types
    return shuffleString(password);
  }

• src/handlers/generate-password.handler.ts:30-37 (helper)

  Helper function to shuffle the characters in the generated password for randomness.

  function shuffleString(str: string): string {
    const array = str.split('');
    for (let i = array.length - 1; i > 0; i--) {
      const j = Math.floor(Math.random() * (i + 1));
      [array[i], array[j]] = [array[j], array[i]];
    }
    return array.join('');
  }