What does 'receipts' mean in AI, and why does Heidi insist on them?
A receipt is machine evidence that an outcome actually happened: the raw response, the diff, the delivery confirmation. Heidi attaches one to every act because claimed outcomes without proof are how trust in AI dies.
When an AI says 'done,' the only honest follow-up is 'prove it.' Heidi renders the proof next to the claim, and flags acts whose proof cannot be obtained as unverified.
Receipts change the management model: you audit evidence instead of re-doing work, and undo becomes precise instead of hopeful.