JMAP Courier

A TypeScript JMAP client for email that works with any JMAP-compliant provider.

Implements RFC 8620 (JMAP Core) and RFC 8621 (JMAP Mail).

Installation

npm install jmap-courier

Quick Start

import { JMAPClient } from 'jmap-courier';

const client = new JMAPClient({
    name: 'my-account',
    token: 'your-api-token',
    sessionUrl: 'https://api.fastmail.com/jmap/session', // Provider-specific
});

// Fetch session and list mailboxes
await client.fetchSession();
const mailboxes = await client.getMailboxes();

// Search emails
const emailIds = await client.queryEmails({ inMailbox: 'inbox-id' });
const emails = await client.getEmails(emailIds);

// Send an email
await client.sendEmail({
    to: ['recipient@example.com'],
    subject: 'Hello',
    textBody: 'Hello from JMAP Courier!',
});

Provider Session URLs

API Reference

JMAPClient

• fetchSession() - Initialize connection and get account info
• getMailboxes() - List all mailboxes
• getMailboxByRole(role) - Find mailbox by role (inbox, trash, sent, etc.)
• queryEmails(filter?, sort?, limit?) - Search for emails
• getEmails(ids, properties?) - Get emails by ID
• getEmailWithBody(id) - Get full email with body content
• moveEmails(ids, mailboxId) - Move emails to mailbox
• deleteEmails(ids) - Move emails to trash
• markEmailsRead(ids, isRead) - Mark as read/unread
• markEmailsFlagged(ids, isFlagged) - Flag/unflag emails
• sendEmail(params) - Send a new email
• forwardEmail(params) - Forward an email

Credits

Copyright © 2026 Anand Mandapati

Created with AI using Antigravity and Claude Opus.

License

MIT - see LICENSE for details.