API status

What is checked

The synthetic probe (GET /v1/status): every few minutes the gateway sends one short machine-generated Mandarin clip (“你好”, no real voice) to the scoring engine exactly as an assessment would reach it, without an account or credits. A pass means a well-formed scored result came back; it does not measure scoring accuracy. Two failures in a row show as Down; one failure, or under 95% of checks passing in 24 hours, shows as Degraded; no check for three intervals shows as Probe silent. A probe that finds the engine's queue full of customer work is counted as busy, not as a failure.

The language list (GET /v1/capabilities) travels the same path as an assessment: through the website's proxy to the gateway, then to the engine. It does not score audio, so a language can still fail on a specific recording.

Both endpoints are free, need no key and answer with CORS headers, so you can poll them from your own monitoring.

Incidents

Incidents and fixes are posted on the changelog from October 2026; no public incident log was kept before that. The website proxy follows Netlify's own status. If something looks wrong, email nik@toneperfect.app with the X-Request-Id of a failing request.

Architecture, in one line

One server in Nuremberg runs the gateway and the engine; the engine scores one recording at a time and queues up to three more. Failed or refused requests are never charged. There is no uptime commitment (SLA). See capacity.