# OpenCode setup

OpenCode is an open-source coding agent for the terminal. Add Claudech as a custom OpenAI-compatible provider in its config file.

## Before you start

- **A Claudech API key** from [API keys](https://claudech.com/api-keys). API access unlocks after your first purchase.

## Configuration

Save your key in an environment variable:

```bash
export CLAUDECH_API_KEY=sk-...
```

Then add a provider to `opencode.json` in your project, or to `~/.config/opencode/opencode.json` for every project:

```json
{
  "$schema": "https://opencode.ai/config.json",
  "provider": {
    "claudech": {
      "npm": "@ai-sdk/openai-compatible",
      "name": "Claudech",
      "options": {
        "baseURL": "https://api.claudech.com/v1",
        "apiKey": "{env:CLAUDECH_API_KEY}"
      },
      "models": {
        "claude-opus-5-5": { "name": "Claude Opus 5.5" },
        "claude-fable-5-1": { "name": "Claude Fable 5.1" },
        "claude-opus-5": { "name": "Claude Opus 5" },
        "claude-sonnet-5": { "name": "Claude Sonnet 5" }
      }
    }
  },
  "model": "claudech/claude-opus-5-5"
}
```

Start `opencode` and run `/models` to switch between the Claudech models.

## Troubleshooting

| Symptom | Fix |
| --- | --- |
| `401` or "invalid API key" | `CLAUDECH_API_KEY` is not set in the terminal running OpenCode |
| Provider missing from `/models` | Check the JSON is valid and the file is in one of the two locations above |
| `404 model_not_found` | The keys under `models` must be Claudech model ids exactly |
| `402 insufficient_balance` | Top up under [Billing](https://claudech.com/billing) |

See [all integrations](https://claudech.com/docs/integrations) for other tools. Claudech is an independent service and is not affiliated with the makers of OpenCode.

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Source: https://claudech.com/docs/integrations/opencode