How to use Zed with a custom Anthropic or OpenAI-compatible endpoint

Zed is an open-source code editor written in Rust, with an Agent panel built in. Unlike Cursor, Zed lets you configure an Anthropic-compatible provider directly, so claude- model IDs can go through CCSub too. Providers live in Zed's settings.json; the key is stored separately.

Opening settings.json

Open the command palette (Cmd+Shift+P on macOS, Ctrl+Shift+P elsewhere) and run zed: open settings file, or press Cmd+Alt+, on macOS. Plain Cmd+, opens the graphical Settings Editor; the provider configuration below is edited in the JSON file. It lives at ~/.config/zed/settings.json on macOS and Linux and %APPDATA%\Zed\settings.json on Windows.

Option 1: Anthropic-compatible (best for Claude model IDs)

Add a language_models block, or merge into the one you have:

{
  "language_models": {
    "anthropic_compatible": {
      "ccsub": {
        "api_url": "https://www.ccsub.net",
        "available_models": [
          {
            "name": "claude-sonnet-5",
            "display_name": "claude-sonnet-5 (CCSub)",
            "max_tokens": 200000,
            "capabilities": { "tools": true, "images": true }
          }
        ]
      }
    }
  }
}

The model field takes IDs such as claude-sonnet-5; the full list is on the models page. Add one entry to available_models per model you want in the picker.

Option 2: OpenAI-compatible

{
  "language_models": {
    "openai_compatible": {
      "ccsub-openai": {
        "api_url": "https://www.ccsub.net/api/v1",
        "available_models": [
          { "name": "gpt-5.5", "display_name": "gpt-5.5 (CCSub)", "max_tokens": 200000 }
        ]
      }
    }
  }
}

Note that the two api_url values follow opposite rules: Anthropic-compatible has no /v1 (Zed adds /v1/messages itself), while OpenAI-compatible goes all the way to /api/v1 (Zed only adds /chat/completions).

Setting the key

Zed's documentation is explicit: do not put API keys in settings.json. Use one of these instead:

1. The UI. Run agent: open settings and find ccsub under LLM Providers, then paste your CCSub key. You can also create providers from Add Provider here — choose Anthropic for an Anthropic-compatible one.
2. An environment variable. The name is the provider name in upper snake case plus _API_KEY: ccsub reads CCSUB_API_KEY, and ccsub-openai reads CCSUB_OPENAI_API_KEY. Restart Zed after setting it.

Verify

Open the Agent panel, choose a model under ccsub and send a message. Then look for the request on the Usage page of your CCSub dashboard. Comparing editors? See the Cursor guide, or the Cline guide if you prefer staying in VS Code.