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.