uuon.world / legal / api-terms
API terms
Last updated 10 October 2026
These terms add to the Terms of service for programmatic use of api endpoints on uuon.world and clouud.uuon.world.
Authentication
Send your key in the x-api-key header, or a wallet session as Authorization: Bearer. Keys belong to one account; don't share them or put them in public code.
Limits that apply today
| Limit | Value |
|---|---|
| Free API keys | 100 calls per day (daily_limit) |
| Signed-in accounts | 100 free calls (free_calls_limit), then paid calls or CENS |
| Wallet sign-in nonces | 10 per minute per IP address |
| Engine inputs | Validated before any charge; requests over the engine's size limits are refused with 400 and not billed |
We may add or tighten limits to protect the service and will document them here.
Pricing and billing
Current prices are always at GET /billing/pricing. Paid engine calls can be paid with CENS (X-Pay-With: cens); a call that fails with a server error is refunded in CENS.
Versioning and deprecation
Endpoints are unversioned today. Breaking changes will be announced at least [NOTICE PERIOD, e.g. 30 days] ahead in the docs and, for accounts with an email address, by email. Additive changes (new fields, new endpoints) can happen at any time.
Availability
The APIs are provided on a best-effort basis. There is no service level agreement (SLA) and no uptime guarantee. Live status is on the status panel.
Support
support@uuon.world. Security issues: security@uuon.world, see Security.