OpenCode

Browser CORS + self-hosted only

OpenCode does not allow browser-origin requests, so it requires the proxy, which only exists on self-hosted deployments. On the hosted instance there is no proxy and OpenCode can't be reached. See Compatibility and Configuration.

OpenCode offers two access lanes with different pricing and endpoints:

• OpenCode Zen: the pay-per-use gateway. Deposit a balance and pay per token; there is no monthly fee. Endpoint: https://opencode.ai/zen/v1.
• OpenCode Go: the subscription lane. A flat monthly fee with rolling usage caps. Endpoint: https://opencode.ai/zen/go/v1.

Both lanes expose models through three different protocols, so there is no single preset; configure it per model through the Custom preset instead. The official model list, including the endpoint protocol each model expects, lives at https://opencode.ai/docs/zen/ for OpenCode Zen and at https://opencode.ai/docs/go/ for OpenCode Go.

Setup (self-hosted only):

1. Preset: Custom
2. Provider: pick the protocol the model speaks:
   • OpenAI Compatible for models served over /responses or /chat/completions (e.g. DeepSeek, GLM, Kimi)
   • Anthropic Claude for models served over /messages (e.g. Qwen, MiniMax)
3. Endpoint URL: https://opencode.ai/zen/v1 (Zen) or https://opencode.ai/zen/go/v1 (Go), base URL only; the provider appends the path
4. API key: create one at https://opencode.ai/auth
5. Model: type the model id (e.g. qwen3.8-max). If the model list doesn't load, a free-text field appears.
6. Advanced → enable Proxy API requests through this server (OpenCode does not allow browser-origin requests)
7. For OpenAI Compatible models served over /chat/completions, enable Use old /chat/completions endpoint in Advanced.
8. Advanced → Custom Headers: add x-opencode-session with value $SESSION_ID.
9. Test Connection, Apply

The x-opencode-session header is required

You must add the x-opencode-session: $SESSION_ID custom header. OpenCode uses it to identify the conversation and enable prompt caching across your requests. Without it, requests may fail.