Under the hoodTier: how much it should matter to you
2Useful: my rating, 1 to 5
3Signal: worth watching, 1 to 5
Usage & LimitsArea: what it touches
Internal ChangesKind: in v2.1.227,
Internal ChangesSection of the release
What
Each user message now gets its own prompt identifier, sent as a cc_prompt_id segment in the billing attribution header and in request metadata, so usage can be attributed to individual prompts.
Details
Added to the attribution header only for first-party authentication, and only when the value matches a UUID shape.
Removed again when transcripts are exported or serialised, so it does not appear in saved conversation files.
Evidence
cc_prompt_id
Strings lifted out of the shipped bundle, so the claim above can be checked against them.