x-tenant-api-key header on quotes, swap limits, and order creation; tracking by UUID needs no credentials at all. There’s nothing to register and no session to maintain. Vane’s shared tenant key, shown in the Quickstart, is all a normal integration needs. If you need custom parameters or separate order tracking, such as for a wallet integration, contact support for a dedicated key. A 401 on these calls points at the key header, whatever the message says (Authentication).
Accountless orders come back with userId: null, and the uuid on the 201 response is your only handle on them. The UUID alone grants read access to the order, so persist it server-side and treat it like a secret.
Wallet sign-in (SIWX) is an optional layer on top. The user’s wallet signs a challenge nonce, POST /auth/siwx/verify returns a JWT pair, and orders created with the token are linked to the user.
Start with the key alone; backends, bots, and embedded swap flows rarely need more. Add SIWX when people use your app repeatedly and expect their history to follow them, or skip SIWX entirely and keep the order history yourself by storing UUIDs. The swap flow is identical in both modes, so adding it later changes nothing you’ve built.
The key header and the full SIWX flow are in Authentication.