# namera mcp serve

> Documentation index: [llms.txt](https://namera.ai/llms.txt).

Source: https://namera.ai/docs/cli/reference/mcp/serve

Start the local stdio MCP server for an agent client.

Start the local stdio MCP server for an agent client.

## Usage [#usage]

```sh
namera mcp serve --profile default
```

## Output [#output]

This is a long-running protocol process, not a command that prints a result.
Stdout contains MCP messages only; diagnostics and authorization instructions
go to stderr. The client starts and stops the process. Closing stdin ends it.

## Options [#options]

### --profile [#--profile]

- **Type:** `string`
- **Default:** `default`

Choose the MCP connection name. This is separate from ordinary CLI profiles,
whose default is `personal`. Use the same name for `serve`, `login`, `status`,
and `logout`.

### --host [#--host]

- **Type:** absolute API URL
- **Default:** `https://api.namera.ai`

Choose the API origin for this MCP connection. The origin and profile together
identify its saved credentials. Use HTTPS, or a loopback HTTP origin for local
development. `NAMERA_API_URL` does not override this option on MCP commands.

### --max-gas-cost-wei [#--max-gas-cost-wei]

- **Type:** non-negative integer string, in wei
- **Default:** sponsored operations only

Approve a maximum gas cost for self-funded executions. MCP tools cannot raise
this process-level ceiling. Omit it unless you intend to allow the agent to pay
gas from the account.

```sh
namera mcp serve --profile default --max-gas-cost-wei 1000000000000000
```

`--output` and `--quiet` do not turn the stdio protocol into ordinary command
output. Do not redirect stdout into a log file.

## Authorization [#authorization]

Register this command with your MCP client instead of running a daemon manually.
The first authenticated tool call starts browser authorization when needed.
After approving it, retry the tool. Ordinary CLI login and `NAMERA_API_KEY` do
not authorize MCP.

Supported protocol versions are `2026-07-28`, `2025-11-25`, and `2025-06-18`.
Negotiation is automatic; there is no protocol-version flag.

## Errors [#errors]

Failures exit nonzero and are written to stderr. With `--output json`, inspect
`error.code` and `error.nextStep`. See [Output and Errors](https://namera.ai/docs/cli/output-and-errors).