OpenAI-compatible chat completions across many open models, paid per call in USDC with no API key. POST { model, messages, max_tokens? } and pick model from GET /v1/models (fast, smart, code, reasoning and 70B tiers, among others). The price is set from the model's rates and your request size, so short prompts on small models cost the least; the 402 shows the exact amount before you pay. Hero: GET /heroes/chat-completions.