Uptime Kuma can show UP while your endpoint reports a failed dependency. If the endpoint still answers HTTP 200, add a check for the specific response field that matters. A broad keyword such as ok can miss the failure too.
The example below uses four small test responses and records what 12 real Uptime Kuma monitors reported. Use it before trusting the green badge on a self-hosted app or a service you just shipped.
Source checks and local experiment: September 9, 2026. Tested with Uptime Kuma 2.5.3. The responses are synthetic; no production database was disconnected.
The quick fix: For the example response below, select HTTP(s) – JSON Query, set the query to checks.database, the condition to ==, and the expected value to ok. Then deliberately return down and confirm the monitor changes state. Test delivery to your notification channel separately.
See the recorded results · Configure the monitor · Run the lab · Check the alert path · FAQ
