> ## Documentation Index
> Fetch the complete documentation index at: https://sendmux.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Codex MCP setup

> Configure Sendmux MCP in Codex.

Use this page to connect Sendmux MCP to your AI client.

## Hosted OAuth

Use the hosted endpoint when the client supports remote MCP OAuth:

```text theme={null}
https://mcp.sendmux.ai/mcp
```

Add this to `~/.codex/config.toml` or a trusted project `.codex/config.toml`.

```toml theme={null}
[mcp_servers.sendmux]
url = "https://mcp.sendmux.ai/mcp"
```

Then authenticate:

```bash theme={null}
codex mcp login sendmux
```

## Local stdio

Install the local package once:

```bash theme={null}
pip install sendmux-mcp
```

Use a mailbox key for Mailbox or Sending:

```bash theme={null}
export SENDMUX_MBX_KEY=smx_mbx_...
```

Use a root key for Management:

```bash theme={null}
export SENDMUX_ROOT_KEY=smx_root_...
```

Run Codex with `SENDMUX_API_KEY` already set, then use `env_vars` so the value stays outside the config file.

```toml theme={null}
[mcp_servers.sendmux_mailbox]
command = "sendmux-mcp-mailbox"
env_vars = ["SENDMUX_API_KEY"]
```

## Private HTTP

Start a local HTTP MCP server:

```bash theme={null}
SENDMUX_API_KEY=smx_mbx_... \
SENDMUX_MCP_HTTP_BEARER_TOKEN=local-mcp-token \
sendmux-mcp-mailbox --transport http --host 127.0.0.1 --port 8765
```

Use `http://127.0.0.1:8765/mcp` as the client URL.

```toml theme={null}
[mcp_servers.sendmux_local]
url = "http://127.0.0.1:8765/mcp"
bearer_token_env_var = "SENDMUX_MCP_HTTP_BEARER_TOKEN"
```