API Management service nothing is calling
An API Management service with no gateway requests at all over the window, billing its provisioned units in full.
Why it happens
An API Management service bills a fixed hourly rate per unit for as long as it exists, whether or not a single request reaches it: a Developer unit is about $48 a month, Standard about $687, and Premium about $2,795. It cannot be stopped or deallocated the way a virtual machine can, so the only way to stop the charge is to delete it, which takes 30 to 45 minutes and destroys the API definitions, custom domains, certificates and subscription keys along with it. The rule reports a service only when the gateway handled exactly zero requests across the window, never merely few. The Consumption tier is skipped because it bills per call and an idle one costs nothing. WebSocket traffic reports through separate preview metrics, so a WebSocket-only API may not register here, which is one reason this is reported for a person to confirm rather than acted on.
What the agent does about it
An API Management service with no gateway requests at all over the window, billing its provisioned units in full.
It will not fix this one
It reports this and takes no action. A check only earns the right to change something once the action behind it can re-read live state before it fires and knows the way back.
Related checks
Idle virtual machine
A running VM whose CPU and network have been near zero for the whole window.
Oversized virtual machine
A running VM whose sustained peak fits comfortably inside the next size down.
Unattached managed disk
A managed disk attached to nothing, billing its full provisioned size every month.