add_labels

Instructions

Implementation Reference

• src/jmap-client.ts:884-911 (handler)

  The `addLabels` method on JmapClient: builds a JMAP patch to add specific mailboxIds to an email's mailboxIds field and sends an Email/set request. This is the core handler that executes the label-adding logic via the Fastmail JMAP API.

  async addLabels(emailId: string, mailboxIds: string[]): Promise<void> {
    const session = await this.getSession();
  
    // Build patch object to add specific mailboxIds
    const patch: Record<string, any> = {};
    mailboxIds.forEach(mailboxId => {
      patch[`mailboxIds/${mailboxId}`] = true;
    });
  
    const request: JmapRequest = {
      using: ['urn:ietf:params:jmap:core', 'urn:ietf:params:jmap:mail'],
      methodCalls: [
        ['Email/set', {
          accountId: session.accountId,
          update: {
            [emailId]: patch
          }
        }, 'addLabels']
      ]
    };
  
    const response = await this.makeRequest(request);
    const result = this.getMethodResult(response, 0);
  
    if (result.notUpdated && result.notUpdated[emailId]) {
      throw new Error('Failed to add labels to email.');
    }
  }

• src/index.ts:1475-1493 (handler)

  The tool handler for 'add_labels' in the MCP request router: extracts emailId and mailboxIds from args, validates inputs, calls client.addLabels(), and returns a success message.

  case 'add_labels': {
    const { emailId, mailboxIds } = args as any;
    if (!emailId) {
      throw new McpError(ErrorCode.InvalidParams, 'emailId is required');
    }
    if (!mailboxIds || !Array.isArray(mailboxIds) || mailboxIds.length === 0) {
      throw new McpError(ErrorCode.InvalidParams, 'mailboxIds array is required and must not be empty');
    }
    const client = initializeClient();
    await client.addLabels(emailId, mailboxIds);
    return {
      content: [
        {
          type: 'text',
          text: `Labels added successfully to email`,
        },
      ],
    };
  }

• src/index.ts:680-698 (schema)

  The input schema registration for the 'add_labels' tool, defining the required emailId (string) and mailboxIds (array of strings) parameters.

  {
    name: 'add_labels',
    description: 'Add labels (mailboxes) to an email without removing existing ones',
    inputSchema: {
      type: 'object',
      properties: {
        emailId: {
          type: 'string',
          description: 'ID of the email to add labels to',
        },
        mailboxIds: {
          type: 'array',
          items: { type: 'string' },
          description: 'Array of mailbox IDs to add as labels',
        },
      },
      required: ['emailId', 'mailboxIds'],
    },
  },

• src/index.ts:680-698 (registration)

  Registration of the 'add_labels' tool in the ListToolsRequestSchema handler, declaring its name, description, and input schema.

  {
    name: 'add_labels',
    description: 'Add labels (mailboxes) to an email without removing existing ones',
    inputSchema: {
      type: 'object',
      properties: {
        emailId: {
          type: 'string',
          description: 'ID of the email to add labels to',
        },
        mailboxIds: {
          type: 'array',
          items: { type: 'string' },
          description: 'Array of mailbox IDs to add as labels',
        },
      },
      required: ['emailId', 'mailboxIds'],
    },
  },