> ## Documentation Index
> Fetch the complete documentation index at: https://docs.layerx1.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Claude Code on Layer X1.

> Claude Code speaks the Anthropic Messages dialect natively — pointing it at Layer X1 is four environment variables, or one command.

## One command

```sh theme={null}
npx layerx1 setup --tool claude-code --key lx1_your_key
```

The CLI writes the config below into `~/.claude/settings.json`, backs up what was there,
and is safe to re-run. See [CLI](/cli) for everything it can do.

## By hand

Set four variables — in `~/.claude/settings.json` under `env`, or exported in your shell:

<CodeGroup>
  ```json settings.json theme={null}
  {
    "env": {
      "ANTHROPIC_BASE_URL": "https://api.layerx1.com",
      "ANTHROPIC_AUTH_TOKEN": "lx1_your_key",
      "ANTHROPIC_MODEL": "lx1-sonnet-4.6",
      "ANTHROPIC_SMALL_FAST_MODEL": "lx1-glm-4.7-flash"
    }
  }
  ```

  ```sh shell theme={null}
  export ANTHROPIC_BASE_URL=https://api.layerx1.com
  export ANTHROPIC_AUTH_TOKEN=lx1_your_key
  export ANTHROPIC_MODEL=lx1-sonnet-4.6
  export ANTHROPIC_SMALL_FAST_MODEL=lx1-glm-4.7-flash
  ```
</CodeGroup>

* `ANTHROPIC_BASE_URL` — the gateway **origin only**. Do **not** append `/v1`; Claude Code
  adds `/v1/messages` itself.
* `ANTHROPIC_AUTH_TOKEN` — your `lx1_` key.
* `ANTHROPIC_MODEL` — the main model. `lx1-sonnet-4.6` for the premium ceiling (vision,
  top reasoning), or `lx1-gpt-oss-120b` for a fast everyday driver. Any
  [catalog id](/models) works.
* `ANTHROPIC_SMALL_FAST_MODEL` — the model for quick auxiliary calls;
  `lx1-glm-4.7-flash` keeps them near-free.

## Verify

Start `claude` and run a trivial prompt. To confirm the wiring end-to-end without Claude
Code in the loop:

```sh theme={null}
npx layerx1 test --key lx1_your_key
```

## Troubleshooting

* **Still using your Anthropic account?** If you were signed in before, run `/logout` once
  so Claude Code picks up `ANTHROPIC_AUTH_TOKEN` instead of the stored session.
* **404s on every call?** The base URL probably includes `/v1` — use the bare origin.
* **401 unauthorized?** The key must be in `ANTHROPIC_AUTH_TOKEN` (not
  `ANTHROPIC_API_KEY`) for a gateway base URL.
* **Context meter looks off?** Claude Code budgets with
  [count\_tokens](/api/count-tokens), which returns an estimate — billing always uses exact
  usage from real responses.

<Note>
  Model choice is per-variable, so you can run the premium model as the main driver and
  keep the fast tier on auxiliary calls — every plan includes both.
</Note>