HTML version: https://cooperemail.com/guides/claude-code-email-inbox

Claude Code

# Email inbox for Claude Code via Cooper MCP

Yes, Cooper Email gives Claude Code its own email inbox over the hosted MCP server at https://cooperemail.com/mcp. One POST to https://cooperemail.com/api/v1/onboard returns an API key once and username@cooperemail.com, and claude mcp add connects that server with the key. Free: $0, no card, 5 inboxes, 5,000 emails/month, and no separate daily cap.

```
curl -s 'https://cooperemail.com/api/v1/onboard?ref=claude-code-page' \
  -H 'content-type: application/json' \
  -H 'X-Client: curl' \
  -d '{"username":"claude-code-agent","display_name":"Claude Code"}'
```

## Connect Claude Code over MCP

Export the api_key as COOPER_API_KEY. It is shown once. The command below is the manual MCP add. The JSON is the same server in a project .mcp.json file. type http is required. Replace coop_live_YOUR_KEY with that key. If Claude Code is already connected without a key, call cooper_onboard with username claude-code-agent. The plugin install is a separate path on https://cooperemail.com/for/claude-code.

```
claude mcp add --transport http cooper-email https://cooperemail.com/mcp --header "Authorization: Bearer $COOPER_API_KEY"

# .mcp.json
{
  "mcpServers": {
    "cooper-email": {
      "type": "http",
      "url": "https://cooperemail.com/mcp",
      "headers": {
        "Authorization": "Bearer coop_live_YOUR_KEY"
      }
    }
  }
}
```

[Claude Code plugin install](/for/claude-code) · [MCP](/docs/mcp) · [Pricing](/pricing) · [Docs](/docs) · [llms.txt](/llms.txt)

Operator: Avatar 8 LLC (ops@avatar33.com).

Agents ask

## FAQ

### How does Claude Code get an email inbox through Cooper MCP?

Run the signup curl, save the api_key, then run claude mcp add --transport http cooper-email [https://cooperemail.com/mcp](https://cooperemail.com/mcp) --header "Authorization: Bearer $COOPER_API_KEY". Cooper Email returns username@cooperemail.com. If the server is already connected and has no key, call cooper_onboard instead of the curl.

### Where does the Claude Code MCP config go?

A project .mcp.json lists mcpServers.cooper-email with type http, url [https://cooperemail.com/mcp,](https://cooperemail.com/mcp,) and an Authorization bearer. That file is the manual project config. The plugin path is [https://cooperemail.com/for/claude-code.](https://cooperemail.com/for/claude-code.)

### What if the username claude-code-agent is already taken?

POST /api/v1/onboard returns HTTP 409 inbox_exists when that username is taken. Pick another name that still starts with claude-code-, or check first with GET [https://cooperemail.com/api/v1/usernames/check?name=claude-code-agent.](https://cooperemail.com/api/v1/usernames/check?name=claude-code-agent.) The check does not say who holds a name.

### What does Cooper Email Free include for Claude Code?

Free: $0, no card, 5 inboxes, 5,000 emails/month, and no separate daily cap. Custom domains are not included on Free (0). They start on Starter ($12/month).

[More answers on the FAQ](/faq)