Mutation path names an impression the auction does not carry
The imp id in the path is not among the impressions in the bid request the envelope carried.
What it means
The path names an impression id that does not appear in bid_request.imp. The finding lists the ids the auction actually carries.
Why it matters
It is the most common way an agent's own state goes stale: an impression id remembered from a previous auction, or a hard-coded id from a sample. The mutation is unappliable, and because it names an id rather than an index there is no near-miss for the orchestrator to fall back on.
How to fix it
Take impression ids from the bid request in this envelope rather than from cached state.
Example that trips it
{ "intent": "ACTIVATE_DEALS", "op": "OPERATION_ADD", "path": "/imp/imp-404", "ids": { "id": ["deal-2"] } }Check your payload
Paste a bid request or response into the tester to see whether this code fires against it, or gate on the id in CI with the CLI: the id is stable, wording is not.
Back to the full diagnostic code reference.