IMAP Mini MCP

A lightweight MCP (Model Context Protocol) server for reading IMAP email and creating draft replies. Works with any standard IMAP server (Gmail, Outlook, Fastmail, etc.) and local bridges like ProtonMail Bridge.

Agents can read, search, move, star, and organize emails, and compose drafts — but cannot send or delete emails.

See CHANGELOG.md for recently added features.

Workflow Recommendation

I highly recommend using a speech-to-text tool (e.g. SuperWhisper on Mac or Whisperflow on Windows) and connecting your AI desktop application (Claude, Codex, etc.) to this MCP server. That way you can converse with your email inbox using speech, which will dramatically speed up your workflow.

How to Use

Agent configuration

Add to your MCP client config (e.g. claude_desktop_config.json):

{
  "mcpServers": {
    "imap-mini-mcp": {
      "command": "node",
      "args": ["/path/to/imap-mini-mcp/dist/index.js"],
      "env": {
        "IMAP_HOST": "imap.example.com",
        "IMAP_USER": "you@example.com",
        "IMAP_PASS": "your-password"
      }
    }
  }
}

The args path must point to the built dist/index.js. Add any optional variables to the env block as needed.

Environment variables

| Variable | Required | Default | Description | |---|---|---|---| | IMAP_HOST | yes | — | IMAP server hostname (e.g. imap.gmail.com) | | IMAP_USER | yes | — | Email address or username | | IMAP_PASS | yes | — | Password or app-specific password | | IMAP_PORT | no | 993 | IMAP server port | | IMAP_SECURE | no | true | Use TLS for the connection | | IMAP_STARTTLS | no | true | Upgrade to TLS via STARTTLS (when IMAP_SECURE=false) | | IMAP_TLS_REJECT_UNAUTHORIZED | no | true | Reject self-signed TLS certificates |

For most providers (Gmail, Outlook, Fastmail), the defaults work — just set host, user, and password.

For ProtonMail Bridge — all five settings below are required (the bridge listens on localhost without TLS, uses a self-signed certificate, and does not support STARTTLS):

IMAP_HOST=127.0.0.1
IMAP_PORT=1143
IMAP_SECURE=false
IMAP_STARTTLS=false
IMAP_TLS_REJECT_UNAUTHORIZED=false

Or as MCP client config:

{
  "mcpServers": {
    "imap-mini-mcp": {
      "command": "node",
      "args": ["/path/to/imap-mini-mcp/dist/index.js"],
      "env": {
        "IMAP_HOST": "127.0.0.1",
        "IMAP_PORT": "1143",
        "IMAP_SECURE": "false",
        "IMAP_STARTTLS": "false",
        "IMAP_TLS_REJECT_UNAUTHORIZED": "false",
        "IMAP_USER": "you@proton.me",
        "IMAP_PASS": "your-bridge-password"
      }
    }
  }
}

Tools

Every email is identified by a composite id (YYYY-MM-DDTHH:mm:ss.<Message-ID>) that is globally unique and stable across folder moves. Use the id returned by find_emails to fetch content, download attachments, move emails, or create reply drafts. Action tools accept an optional mailbox hint for faster lookup; if omitted, all folders are searched.

find_emails

Search and filter emails. All parameters are optional — calling with no parameters returns all emails from INBOX, sorted newest-first.

| Parameter | Type | Default | Description | |---|---|---|---| | after | string | — | Only emails after this time. Relative ("30m", "2h", "7d") or ISO date ("2026-02-20") | | before | string | — | Only emails before this time. Same formats as after | | from | string | — | Substring match on sender address (e.g. "alice@example.com", "@stripe.com") | | subject | string | — | Substring match on subject line | | unread_only | boolean | false | Only return unread emails | | has_attachment | boolean | false | Only return emails with attachments | | folder | string | "INBOX" | Folder to search | | limit | number | — | Maximum number of results (newest first) |

Examples:

| Use case | Parameters | |---|---| | Last 24 hours | {after: "24h"} | | Last 7 days, max 10 | {after: "7d", limit: 10} | | Unread emails | {unread_only: true} | | From a domain | {from: "@stripe.com"} | | With attachments, last month | {after: "30d", has_attachment: true} | | Specific sender, in Sent folder | {from: "alice@example.com", folder: "Sent"} |

Other tools

| Tool | Description | Key parameters | |---|---|---| | list_starred_emails | Starred emails across all folders | — | | fetch_email_content | Full email content by id | id, mailbox? | | fetch_email_attachment | Download an attachment | id, attachment_id, mailbox? | | list_folders | List all folders | — | | create_folder | Create a new folder | path | | move_email | Move an email to another folder | id, destination_folder, source_folder? | | bulk_move_by_sender_email | Move all emails from a sender | sender, source_folder, destination_folder | | bulk_move_by_sender_domain | Move all emails from a domain | domain, source_folder, destination_folder | | star_email | Star an email | id, mailbox? | | unstar_email | Unstar an email | id, mailbox? | | mark_read | Mark an email as read | id, mailbox? | | mark_unread | Mark an email as unread | id, mailbox? | | create_draft | Create a new draft | to, subject, body, cc?, bcc?, in_reply_to? | | draft_reply | Create a reply draft from an existing email | id, body, reply_all?, mailbox? | | update_draft | Replace an existing draft (Drafts folder only) | id, to, subject, body, cc?, bcc?, in_reply_to? |

Troubleshooting

"IMAP connection closed unexpectedly" or "Server disconnected"

This almost always means the server rejected the connection due to a TLS/STARTTLS mismatch. Verify these environment variables are set correctly in your MCP client config:

| Variable | Check | |---|---| | IMAP_HOST | Correct hostname or IP | | IMAP_PORT | Matches your server (993 for TLS, 143/1143 for plain) | | IMAP_SECURE | true for port 993, false for plain connections | | IMAP_STARTTLS | false if your server does not support STARTTLS | | IMAP_TLS_REJECT_UNAUTHORIZED | false if your server uses a self-signed certificate |

Local IMAP bridges (e.g. ProtonMail Bridge) typically require IMAP_SECURE=false, IMAP_STARTTLS=false, and IMAP_TLS_REJECT_UNAUTHORIZED=false. See the ProtonMail Bridge config example in the Environment variables section above.

"IMAP authentication failed"

Check that IMAP_USER and IMAP_PASS are correct. Some providers (e.g. Gmail) require an app-specific password rather than your account password.

"Cannot reach IMAP server — connection refused"

The IMAP server is not running or not listening on the configured host and port. For local bridges, make sure the bridge application is running.

Development

Build and run

npm install
npm run build

Local development with .env

For running the server directly (outside of an MCP client), copy .env.example to .env and fill in your credentials, then:

npm start

When used through an MCP client, credentials are provided via the client config's env block instead.

Testing

Tests use vitest and mock the IMAP layer — no real server connection is needed:

npm test             # run once
npm run test:watch   # watch mode
npm run lint         # type-check only

License

MIT