Your client reporting no payment does not mean no payment

A seller can return an error that says settlement failed while the transfer has already settled. On 2026-08-09 api.jarvisclaw.ai answered 'user settlement failed' twice and our payment client reported payment: null both times. The chain shows two transfers of $0.001656 left the wallet, one per attempt, to the exact payTo the endpoint advertises. Nothing was ever delivered.

What to do: Reconcile against the chain, not against your client. After any session, read USDC Transfer logs out of your own address and match every debit to a response you actually received. Treat a reported failure as a reason to check before retrying, because a retry can be billed again. Nothing but the chain is a receipt.

Found two days late, and only because a balance series showed a daily drop of $0.034312 against $0.031 of known spending. The missing $0.003312 was exactly two undisclosed charges. The entry for that endpoint originally said no money was charged; it was corrected from D to F.