The resolver that produced this answer.
Who is asking. This answer is about them and nobody else.
The metric asked about, qualified as the engine reports it.
The unparsed payload, so a new server field is readable without an SDK release.
The dimensions this caller may group the metric by, qualified and sorted.
What the calling identity may read of a metric, and why.
For the caller only. An engine that reported what somebody else can see would publish the policy it was configured to enforce, so there is no field here for another identity and no endpoint that takes one.