# Proving the tool-call ObservationHandler fires once per call, not twice

startCount before call: 4
startCount after call:  5
fired this call:        1

An earlier version of ObservabilityConfig wired this same handler two ways at once
(a plain @Bean, plus the same instance again inside an ObservationRegistryCustomizer).
Boot's ObservationAutoConfiguration picks up both independently, so every call logged
twice -- verified by running it that way first. See ObservabilityConfig's Javadoc.