Provider Routing
Transfo automatically selects the best AI provider. You never choose — it's fully automatic.
Priority Chain
1. Apple Intelligence (local, on-device)
2. OpenRouter
3. Google Gemini
4. OpenAI
Apple Intelligence (Local)
Used automatically for simple prose tasks when running on macOS 26+ with Apple Intelligence available. These recipes are eligible for local processing:
- Summarize
- Rewrite Pro
- Explain Code
- Extract Action Items
- Fix Grammar
- Translate
Input limit for local: 2,000 characters. Longer inputs always use a remote provider.
Automatic Failover
If you configure multiple API keys, Transfo uses them as a fallback chain:
| What happens | Transfo's response |
|---|---|
| OpenRouter rate limited | → Automatically tries Gemini |
| Gemini times out | → Automatically tries OpenAI |
| OpenAI server error | → Shows error (end of chain) |
| Invalid API key | → Shows error immediately (not retryable) |
Retryable errors (triggers failover): Rate limit, timeout, network error, server error, empty output Non-retryable errors (stops immediately): Invalid key, missing key