Fastmail MCP Server

Instructions

Implementation Reference

• src/index.ts:1114-1129 (handler)

  MCP server tool handler for 'bulk_delete' that validates input and delegates to JmapClient.bulkDelete
  case 'bulk_delete': { const { emailIds } = args as any; if (!emailIds || !Array.isArray(emailIds) || emailIds.length === 0) { throw new McpError(ErrorCode.InvalidParams, 'emailIds array is required and must not be empty'); } const client = initializeClient(); await client.bulkDelete(emailIds); return { content: [ { type: 'text', text: `${emailIds.length} emails deleted successfully (moved to trash)`, }, ], }; }
• src/jmap-client.ts:727-762 (handler)

  Core JMAP implementation of bulkDelete that moves multiple emails to the trash mailbox using Email/set update with mailboxIds
  async bulkDelete(emailIds: string[]): Promise<void> { const session = await this.getSession(); // Find the trash mailbox const mailboxes = await this.getMailboxes(); const trashMailbox = mailboxes.find(mb => mb.role === 'trash') || mailboxes.find(mb => mb.name.toLowerCase().includes('trash')); if (!trashMailbox) { throw new Error('Could not find Trash mailbox'); } const trashMailboxIds: Record<string, boolean> = {}; trashMailboxIds[trashMailbox.id] = true; const updates: Record<string, any> = {}; emailIds.forEach(id => { updates[id] = { mailboxIds: trashMailboxIds }; }); const request: JmapRequest = { using: ['urn:ietf:params:jmap:core', 'urn:ietf:params:jmap:mail'], methodCalls: [ ['Email/set', { accountId: session.accountId, update: updates }, 'bulkDelete'] ] }; const response = await this.makeRequest(request); const result = response.methodResponses[0][1]; if (result.notUpdated && Object.keys(result.notUpdated).length > 0) { throw new Error('Failed to delete some emails.'); } }
• src/index.ts:608-622 (schema)

  Input schema definition for the bulk_delete tool, specifying required emailIds array
  { name: 'bulk_delete', description: 'Delete multiple emails (move to trash)', inputSchema: { type: 'object', properties: { emailIds: { type: 'array', items: { type: 'string' }, description: 'Array of email IDs to delete', }, }, required: ['emailIds'], }, },
• src/index.ts:1142-1142 (registration)

  Tool listed in check_function_availability response for email capabilities
  'get_mailbox_stats', 'get_account_summary', 'bulk_mark_read', 'bulk_move', 'bulk_delete'