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

# Model providers and routes

> Built-in CMX upstream provider IDs, native credentials, and route selection.

# Model providers and routes

A **model provider** is the service that answers a request from your coding client. A **coding client** is Codex, OpenCode, Claude Code, Aider, Antigravity CLI, or Cline. Connect the client first using its [client guide](/providers/overview). Its normal sign-in or API key remains with that client; CMX does not create a provider account or save provider keys.

CMX has these built-in upstream IDs in the current source:

| ID            | Service or route                               |
| ------------- | ---------------------------------------------- |
| `openai`      | OpenAI API                                     |
| `anthropic`   | Anthropic API                                  |
| `openrouter`  | OpenRouter                                     |
| `gemini`      | Google Gemini API                              |
| `cloudcode`   | Google CloudCode route used by Antigravity CLI |
| `deepseek`    | DeepSeek                                       |
| `groq`        | Groq                                           |
| `mistral`     | Mistral                                        |
| `togetherai`  | Together AI                                    |
| `perplexity`  | Perplexity                                     |
| `xai`         | xAI                                            |
| `ollama`      | Local Ollama at `127.0.0.1:11434` by default   |
| `commandcode` | Command Code                                   |
| `opencode`    | OpenCode Zen                                   |
| `opencode-go` | OpenCode Go                                    |
| `cline`       | Cline's API route                              |

A built-in ID means CMX knows an upstream endpoint shape. It does **not** mean your coding client has credentials, that every model works, or that every protocol is compressed. Credentials and available models come from the native client and provider. Check readiness with `cmx providers <client> list`, then connect an ID that the client actually shows. For example:

```bash theme={null}
cmx providers codex list
cmx providers codex connect api
```

Here `api` is a **Codex connection ID**, while `openai` is a **CMX upstream ID**. Those names serve different purposes. For OpenCode, the displayed provider ID is the one to pass to `cmx providers opencode connect <provider-id>`.

## Connect a service you already use

1. Configure the service's account, API key, and model **inside your coding client**. Use that client's own sign-in flow. For example, Codex can use OpenAI API or ChatGPT sign-in, Claude Code can use Anthropic access, OpenCode can manage several services, and Cline can use Cline's account or its own provider settings.
2. Run `cmx providers <client> list`. If your intended provider is missing or reports missing credentials, finish setup in the native client before changing routing.
3. Run `cmx providers <client> connect <displayed-id>`. Restart the client, make a real request, and check `cmx stats`.
4. To go direct again, run `cmx providers <client> disconnect <displayed-id>` and restart the client. See [Undo and uninstall](/uninstall).

The same workflow covers OpenRouter, DeepSeek, Groq, Gemini, Mistral, Together AI, Perplexity, xAI, Ollama, Command Code, OpenCode Zen/Go, and other configured services **when the client exposes them**. A CMX upstream ID by itself cannot add a provider to a client. For local Ollama, start Ollama first and configure its native endpoint in a compatible client. Use the [client-specific instructions](/providers/overview) for the settings CMX can manage.

## Custom providers

A provider must have a valid direct endpoint. CMX accepts HTTPS upstreams and HTTP only for exact loopback hosts, such as a local Ollama service. A malformed URL or an endpoint pointing back at CMX is rejected. For OpenCode, configure a custom provider's direct endpoint in OpenCode first, then list and connect it through CMX. Do not put provider API keys in CMX's `config.json`.

The documented compression path covers OpenAI Chat Completions, OpenAI Responses, and Anthropic Messages. Native endpoints for other formats can be proxied without compression. See [Custom clients](/providers/custom-agents) and [How compression works](/how-compression-works).


## Related topics

- [Frequently asked questions](/faq.md)
- [Connect OpenCode](/providers/opencode.md)
- [Connect Aider](/providers/aider.md)