Give Claude its own email address
Add Mailly as a custom connector in Claude.ai or Claude Desktop so Claude can read your inbox, save reply drafts and send after you approve.
With Mailly as a custom connector, Claude can read and search a real inbox, save reply drafts and send once you approve the final text. Custom connectors work on Claude.ai and in Claude Desktop; in both, Claude connects to Mailly from Anthropic's cloud, so you don't install or run anything locally and don't need claude_desktop_config.json.
What you get
- A two-way inbox on
@mailly.site, or on your own domain on the Developer plan. - About 70 Mailly tools for threads, drafts, sending, domains, contacts, templates, campaigns and workflows, limited to the permissions you grant.
- Sending under your control: Claude shows the exact text and recipients, and sends only after you confirm.
Get an inbox
Already have a Mailly account? Skip to the next step.
The setup prompt needs an agent that can make HTTP requests, such as Claude Code. In a chat, the quickest path is mailly.site/onboard: choose a name, verify your own email and confirm the address. It's the same flow the agent setup uses.
Add the connector
On Free, Pro and Max plans:
- Go to Customize > Connectors, click + Add, then Add custom connector.
- Name it
Maillyand enter the remote MCP server URLhttps://mcp.mailly.site/mcp. - Under Authentication, choose a sign-in option (not No sign in). For the OAuth client, keep Use Claude's published identity (Recommended): Mailly accepts Claude's published client identity, so you don't need a client ID or secret.
- Leave Request headers empty and click Add.
Free plans can add one custom connector.
On Team and Enterprise plans, an Owner adds the connector first in Organization settings > Connectors (Add, then Custom > Web) with the same URL. Members then open Customize > Connectors, find Mailly and click Connect.
Sign in and choose permissions
When you connect, Mailly's sign-in and consent page opens. Choose what Claude may do:
| Permission | What Claude can do |
|---|---|
mail:read | Read your inboxes, threads, sent mail, drafts and settings. Always granted. |
mail:draft | Save, edit and discard reply drafts. No sending. |
mail:send | Send replies, forwards and new emails you have reviewed. |
workspace:manage | Manage addresses, domains, templates, contacts, campaigns, workflows and webhooks. |
Turn it on in a conversation
Click the + button at the lower left of the chat, select Connectors and switch Mailly on. Connectors are enabled per conversation.
Verify the connection
- Ask Claude: "Use Mailly to list my inbox addresses and my five most recent threads." Claude should call
mailly_list_inbox_addressesandmailly_list_threads. - Send an email from your personal account to your Mailly address, then ask: "Read my latest Mailly thread and save a reply draft. Show me the exact text and don't send it." Claude calls
mailly_read_threadandmailly_save_draft. - Approve the draft in the conversation if you granted
mail:send, or ask Claude to discard it.
Troubleshooting
- Claude doesn't use Mailly: check that the connector is switched on for this conversation under + > Connectors.
- A tool you expected is missing: it needs a permission you didn't grant. Remove the connector under Customize > Connectors and add it again, granting the permission on Mailly's consent page. Mailly never widens an existing grant on its own.
- You need to change the URL or sign-in settings: Claude doesn't edit custom connectors in place. Remove the connector and add it again.
- You can't add a custom connector: on Team and Enterprise plans, ask an Owner to add Mailly in Organization settings. On Free, you may already be using your one custom connector.
- No mail arrives: check the address in the workspace and look in the inbox's Spam folder.
Don't put a Mailly API key in Request headers. An API key carries full account access and bypasses the permissions you choose on the consent page.
Working in a terminal? See Claude Code. For every tool the connector exposes, see Tools.