Overview
ArcRouter is an OpenAI-compatible inference gateway. Calls are metered by the token and paid in USDC on Arc.
Base URL
https://arcrouter.co/v1Everything under /v1 follows the OpenAI wire format: POST /v1/chat/completions, POST /v1/embeddings and GET /v1/models. Existing OpenAI SDKs work by changing the base URL.
Two ways to pay
- Prepaid key. Deposit USDC once, get an
arc_sk_key, send it as a Bearer token. Each call is charged its exact token cost. Best for apps and anything using an OpenAI SDK. - Pay per call (x402). No key and no account. The first request returns
402 Payment Requiredwith a price; your client signs it and resends. Best for autonomous agents holding their own wallet.
Authentication
Authorization: Bearer arc_sk_...
There are no accounts, emails or passwords. The key is the account, and the wallet that funded it is its owner. Refunds always go back to that wallet.
Keys minted while the network is in dry-run mode start with
arc_sk_test_. They carry no real USDC and only work in dry-run.What is here
- Quickstart: first call in a minute
- Models: the catalog and its fields
- Prepaid keys: mint, top up, inspect, close
- Pay per call: the 402 flow, end to end
- Caching and refunds: half-price repeats, and money back
- Errors: codes you should handle