Yes, every answer has receipts. Facts carry their origin, the doc, the call, the thread, and answers cite them, so anyone can check where a claim came from.
Claimed knowledge without evidence is how trust dies. Heidi's answers point at their sources: security-review.md, the eng sync transcript, the call recording. You can follow the receipt and read the original.
The same discipline applies to actions: every act an agent takes records a receipt proving what actually happened.