Azure is the only zero-data-retention route for the gpt-5.6 family, so
its capacity 429s arrive frequently and OpenRouter forwards them inside
an HTTP 200 envelope. Those bypassed the rate controller entirely: a
paced run kept sending a request every three seconds into a throttled
endpoint, failing row by row. An in-envelope 429 now records the same
escalating cooldown as a transport 429, so later acquisitions fail fast
until the deadline passes.
Lars Nolden
4d8a187079