BYOK is available on the Max plan.
Supported providers
| Provider | Env variable | Works with |
|---|---|---|
| Anthropic | ANTHROPIC_API_KEY | Claude Code, OpenCode |
| OpenAI | OPENAI_API_KEY | Codex, OpenCode |
| Google AI | GOOGLE_GENERATIVE_AI_API_KEY | OpenCode |
| OpenRouter | OPENROUTER_API_KEY | OpenCode |
Setup
Add a provider key
Select the provider, paste your API key, and save. You can add keys for multiple providers.
Good to know
- BYOK usage is tracked in Twill for visibility, but you are not billed for it through Twill. Set spending limits directly with your provider.
- Sandbox compute is still covered by your Twill plan.
- If you select an agent and model that requires a provider you have not configured, the task falls back to Twill’s platform credits.