Documentation
X420.ai Docs
Buy prepaid GPT-5.5 credit, create capped API keys, and call an OpenAI-compatible endpoint.
Quickstart
Buy credit, create a capped API key, and make your first call.
API Reference
Endpoint, parameters, headers, model selection, and error codes.
Billing
How prepaid API credits, reservations, and per-key caps work.
Privacy
Provider logging, data minimization, tenant keys, and upstream routing.
FAQ
Common questions answered.
