Atomic Mail

Email infrastructure for AI agents.

CommunityOnlineNo sign-inRU / CISFreeCan modify data

What it can do

  • Read Inbox: List the most recent messages in your inbox (newest first). Returns id, from, to, subject, preview and receivedAt for each. Omit agent_id to use your default inbox.
  • Read Message: Fetch one message: headers plus its body as plain text. Pass the message_id (a JMAP Email id, e.g. from read_inbox or search_messages). Omit agent_id to use your default inbox.
  • Search Messages: Full-text search your mailbox and return matching message summaries (newest first). Omit agent_id to use your default inbox.

What data it sees

Do you need an account

No: the server works without sign-in

Email infrastructure for AI agents. Your agent gets a real mailbox and can send, receive and hold a thread on its own.

The agent solves a proof-of-work challenge and has a working @atomicmail.ai address in about 30 seconds. No signup form, no CAPTCHA, nobody pasting credentials in for it. If the inbox should belong to a person instead, sign in with Google or GitHub over OAuth 2.0, or use a bearer API key for headless setups.

What the agent can do

  • Send and receive mail, create drafts, manage threads
  • Full-text search across the mailbox
  • Poll the inbox and run scheduled jobs
  • Pull one-time passcodes and magic links out of incoming mail, so an agent that hits a verification wall gets through it

Built on JMAP (RFC 8620 and 8621) rather than a bespoke REST API. Models already know the protocol from training, so they write correct calls without an SDK, and batched method calls go over in one round trip. Three tools cover the whole surface: register, jmap_request, help.

How to connect

How to connect Atomic Mail to Claude

The server address to paste into Claude settings:

https://atomicmail--atomicmail.run.tools

  1. Open Claude (claude.ai or the desktop app).
  2. Go to Settings → Connectors.
  3. Click Add custom connector.
  4. Paste the server address copied below into Remote MCP server URL and click Add.
  5. In a chat, click + → Connectors and switch the new connector on.

Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.

Authorization

After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.

How to connect Atomic Mail to ChatGPT

The server address to paste into ChatGPT settings:

https://atomicmail--atomicmail.run.tools

  1. Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
  2. Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
  3. Open Settings → Connectors and click Create.
  4. Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
  5. Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
  6. In a new chat open + → Apps/Connectors and enable the connector.

OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.

Authorization

On first use ChatGPT opens the service's sign-in window. Sign in and approve access.

How to connect Atomic Mail to Cursor

The server address to paste into Cursor settings:

https://atomicmail--atomicmail.run.tools

Fastest: click Open in Cursor below and confirm the prompt.

Manually:

  1. In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
  2. Paste the JSON copied below into ~/.cursor/mcp.json (per project: .cursor/mcp.json in the repo root).
  3. Save the file. The server appears in the MCP list; authorize it there if asked.

Authorization

If the service needs sign-in, an authorize button appears next to the server in the MCP list.

Server tool list (10)

Raw names from tools/list. Only developers need these.

read_inboxList the most recent messages in your inbox (newest first). Returns id, from, to, subject, preview and receivedAt for each. Omit agent_id to use your default inbox.
read_messageFetch one message: headers plus its body as plain text. Pass the message_id (a JMAP Email id, e.g. from read_inbox or search_messages). Omit agent_id to use your default inbox.
search_messagesFull-text search your mailbox and return matching message summaries (newest first). Omit agent_id to use your default inbox.
send_emailCompose and send a plain-text email. Provide to, subject and body; cc, bcc and attachments are optional. Omit agent_id to send from your default inbox.
reply_to_messageReply in-thread to a message. Pass the message_id to reply to and the plain-text body; attachments are optional. Omit agent_id to reply from your default inbox.
list_agentsList the Atomic Mail agents you own. Returns accountId, inboxId, status, reputation, linkedAt, activatedAt. Use an accountId as `agent_id` on the other tools (or omit agent_id to use your default inbox).
searchSearch your mail and return matching results as { results: [{ id, title, url }] }. Pass the matching id to `fetch` to read the full message. Uses your default inbox.
fetchFetch one document by id and return { id, title, text, url, metadata } where text is the full message body. Pass an id returned by `search`. Uses your default inbox.
run_presetRun a bundled JMAP flow by name. `preset` is one of: list_inbox, reply, send_mail, send_mail_attachment, send_mail_blob_attachment. Pass `vars` for any $PLACEHOLDER values the preset needs (e.g. TO, SUBJECT, BODY, MAIL_ID). Omit agent_id to use your default inbox.
helpDocumentation for the Atomic Mail tools and topics. Optional. Topics: overview, tools, agents, auth, advanced, troubleshooting. Omit topic for the overview.