Authenticator App MCP Server

Instructions

Implementation Reference

• src/authenticator.ts:37-51 (handler)

  Core handler function that fetches the 2FA code from the backend API via HTTP request using the access token.

  async get2FACode(website: string, username: string): Promise<Get2FACodeResponse> {
    const url = `${this.baseUrl}/code?website=${encodeURIComponent(website)}&username=${encodeURIComponent(username)}`;
    const response = await fetch(url, {
      headers: {
        Authorization: `Bearer ${this.accessToken}`,
      },
    });
  
    if (!response.ok) {
      const errorBody = await response.text();
      console.error(`HTTP error ${response.status} from ${url}: ${errorBody}`);
      throw new Error(`HTTP error ${response.status}: ${errorBody}`); // Include body in error
    }
    return (await response.json()) as Get2FACodeResponse;
  }

• src/mcp.ts:26-50 (registration)

  Registers the get_2fa_code tool with the MCP server, including input schema and thin wrapper handler that delegates to Authenticator.get2FACode and formats the MCP response.

  this.tool(
    'get_2fa_code',
    'Retrieve the current 2FA code for a username when logging into a website.',
    {
      website: z
        .string()
        .describe('The domain name of the website you need to login, e.g. "github.com"'),
      username: z
        .string()
        .describe(
          'The username or email of the account you need to login, e.g. "john.doe@example.com"'
        ),
    },
    async ({ website, username }, extra) => {
      const res = await this.authenticator.get2FACode(website, username);
      return {
        content: [
          {
            type: 'text',
            text: `The 2FA code is ${res.code}, it will expire in ${res.valid_for} seconds.`,
          },
        ],
      };
    }
  );

• src/mcp.ts:29-38 (schema)

  Zod schema for the tool inputs: website (string) and username (string) with descriptions.

  {
    website: z
      .string()
      .describe('The domain name of the website you need to login, e.g. "github.com"'),
    username: z
      .string()
      .describe(
        'The username or email of the account you need to login, e.g. "john.doe@example.com"'
      ),
  },

• src/authenticator.ts:2-27 (schema)

  TypeScript interfaces defining input parameters and output responses for the authenticator methods, including get2FACode.

  interface Get2FACodeParams {
    website: string;
    username: string;
  }
  
  interface GetPasswordParams {
    website: string;
    username: string;
  }
  
  interface GetAccountListParams {
    website: string;
  }
  
  export interface Get2FACodeResponse {
    code: string;
    valid_for: number;
  }
  
  export interface GetPasswordResponse {
    password: string;
  }
  
  export interface GetAccountListResponse {
    accounts: string[];
  }