# send0 MCP server

> Provides AI agents with dedicated email inboxes to create addresses, receive verification codes, and manage email conversations.

- Repository: https://github.com/send0-dev/send0-v2
- Page: https://hostedmcp.org/servers/send0-dev/send0
- Transport: stdio, remote
- Stars: 0
- License: AGPL-3.0
- Latest version: 0.2.1

## Install

### Claude Code

```sh
claude mcp add --env 'SEND0_API_KEY=<YOUR_SEND0_API_KEY>' send0 -- npx -y @send0/mcp
```

### Cursor (`~/.cursor/mcp.json`)

```json
{
  "mcpServers": {
    "send0": {
      "command": "npx",
      "args": [
        "-y",
        "@send0/mcp"
      ],
      "env": {
        "SEND0_API_KEY": "<YOUR_SEND0_API_KEY>"
      }
    }
  }
}
```

### VS Code (`.vscode/mcp.json`)

```json
{
  "servers": {
    "send0": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@send0/mcp"
      ],
      "env": {
        "SEND0_API_KEY": "<YOUR_SEND0_API_KEY>"
      }
    }
  }
}
```

### VS Code CLI

```sh
code --add-mcp '{"name":"send0","type":"stdio","command":"npx","args":["-y","@send0/mcp"],"env":{"SEND0_API_KEY":"<YOUR_SEND0_API_KEY>"}}'
```

### Claude Desktop (`claude_desktop_config.json`)

```json
{
  "mcpServers": {
    "send0": {
      "command": "npx",
      "args": [
        "-y",
        "@send0/mcp"
      ],
      "env": {
        "SEND0_API_KEY": "<YOUR_SEND0_API_KEY>"
      }
    }
  }
}
```

### Codex

```sh
codex mcp add send0 --env 'SEND0_API_KEY=<YOUR_SEND0_API_KEY>' -- npx -y @send0/mcp
```

### Codex config.toml (`~/.codex/config.toml`)

```toml
[mcp_servers.send0]
command = "npx"
args = ["-y", "@send0/mcp"]

[mcp_servers.send0.env]
SEND0_API_KEY = "<YOUR_SEND0_API_KEY>"
```

### Gemini CLI

```sh
gemini mcp add -s user -e 'SEND0_API_KEY=<YOUR_SEND0_API_KEY>' send0 npx -- -y @send0/mcp
```

### Gemini settings.json (`~/.gemini/settings.json`)

```json
{
  "mcpServers": {
    "send0": {
      "command": "npx",
      "args": [
        "-y",
        "@send0/mcp"
      ],
      "env": {
        "SEND0_API_KEY": "<YOUR_SEND0_API_KEY>"
      }
    }
  }
}
```

## Environment variables

| Name | Required | Secret | Description |
|---|---|---|---|
| `SEND0_API_KEY` | yes | yes | send0 API key (s0_live_…), from https://app.send0.dev |
| `SEND0_BASE_URL` | no | no | API base URL, for a self-hosted send0 |
| `SEND0_INBOX_ID` | no | no | Default inbox (ibx_…) for tools that take an inbox_id |

## Tools (7)

- `create_inbox`
- `list_inboxes`
- `wait_for_email`
- `search_messages`
- `get_message`
- `send_email`
- `reply`

## FAQ

### How can I use send0 with Claude Code?

You can add it using the command: claude mcp add send0 --env SEND0_API_KEY=your_key -- npx -y @send0/mcp

### Can I use a specific inbox by default?

Yes, you can set the SEND0_INBOX_ID environment variable so that tools do not require an inbox_id parameter.

### How does the server handle email content security?

Email bodies are returned inside <untrusted_email> tags to indicate they should be treated as data, and messages flagged for prompt injection include a warning.