Firebase MCP Server

Instructions

Implementation Reference

• src/lib/firebase/authClient.ts:8-30 (handler)

  The core handler function for the 'auth_get_user' tool. It retrieves a user record from Firebase Authentication by either UID or email address and returns it as a formatted MCP content response.

  export async function getUserByIdOrEmail(identifier: string) {
    try {
      let userRecord;
      if (identifier.includes('@')) {
        // メールアドレスで検索
        userRecord = await admin.auth().getUserByEmail(identifier);
      } else {
        // ユーザIDで検索
        userRecord = await admin.auth().getUser(identifier);
      }
      return {
        content: [
          {
            type: 'text',
            text: JSON.stringify(userRecord, null, 2)
          }
        ]
      };
    } catch (error) {
      console.error('Error fetching user:', error);
      throw error;
    }
  }

• src/index.ts:184-193 (schema)

  Input schema definition for the 'auth_get_user' tool, specifying the required 'identifier' parameter as a string.

  inputSchema: {
    type: "object",
    properties: {
      identifier: {
        type: "string",
        description: "User ID or email address"
      }
    },
    required: ["identifier"]
  }

• src/index.ts:181-194 (registration)

  Tool registration in the ListTools response, defining name, description, and input schema for 'auth_get_user'.

  {
    name: "auth_get_user",
    description: "Get a user by ID or email from Firebase Authentication",
    inputSchema: {
      type: "object",
      properties: {
        identifier: {
          type: "string",
          description: "User ID or email address"
        }
      },
      required: ["identifier"]
    }
  },

• src/index.ts:250-251 (registration)

  Switch case in CallToolRequestHandler that dispatches 'auth_get_user' calls to the handler function.

  case 'auth_get_user':
    return getUserByIdOrEmail(args.identifier as string);