Your contractor says the AI did the work. Check the record before you pay.

The work is done, the invoice is in, and the only account of what happened is the contractor's own summary. That is the normal way to buy AI work, and it puts the whole risk on the buyer: you were not in the session, you cannot see which steps ran, and the summary was written by the side being paid. There is a check that takes minutes. When the work ran through Zambo, the verifiable work layer for AI, delivery is a record you can open yourself: every step, its receipt, its timestamp, and an acceptance that stays pending until you make the call.

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Published October 17, 2026. Every record quoted below was read live from zambo.dev on the day this page was written. Updated October 17, 2026. Written against AER-1, IETF Internet-Draft revision 23: draft-zambo-aer1-23. AER-1 is an IETF Internet-Draft, not a finalized standard.

Why "the AI did it" is hard to check today

The deliverable file proves a result exists. It does not show how the result was produced: which steps ran, in what order, at what times, what each step actually returned, or which steps were skipped and written around. The contractor holds all of that, because the session, the tools, and the story all sit on their side of the table. Asking harder questions does not fix the asymmetry; the answers are still claims, delivered by the person the invoice pays.

What fixes it is moving the evidence to neutral ground before the dispute: a record fixed at execution time, at public links, that neither side can edit afterward and either side can open. That is the record a Zambo connection keeps automatically, because every call on it leaves a verifiable receipt when it runs.

The check, in five steps

  1. Ask for the handover link, not the summary. A delivery on the connection arrives as one link: the goal at the top, then the steps in the order they ran. If the contractor cannot produce a link, there is no record, and you are buying the story. Price it that way.
  2. Read the steps against the brief. Each step names its call and carries its own receipt and timestamp. Work that was promised and never ran has no step. Work that ran twice shows twice. The shape of the job is visible before you read a single output.
  3. Open two or three receipts yourself. Pick the steps the payment turns on. Each receipt shows the saved result of that call, saved when it ran. The public verifier recomputes the record in the open: the saved result either still matches its commitment or it does not, and you do not need the contractor's account, or anyone's permission, to run that check.
  4. Read the gaps honestly. Where a step lists its sources, each reads resolved, not_resolved, or not_checked, exactly as recorded. A gap is information, not a scandal: it tells you which parts of the delivery rest on checking and which rest on the contractor's word, and you can ask about each one by name.
  5. Let acceptance be your act. The handover's acceptance state starts at pending, release hint hold. Only the client can accept. Accepting records your decision, the time, and how many steps were checked, and the release hint flips to ok_to_release. That record, not a chat message saying looks good, is what should release the payment.

Worked records: a passed check, and one still waiting

The passed check

Handover 45434a17 delivered four steps of work, each with its own receipt. Its acceptance record at acceptance.json reads: status accepted, decided by the client on October 16, 2026, four of four steps checked, release hint ok_to_release. That is the complete shape of a delivery a buyer verified and then paid against: the steps were openable, the buyer checked them, and the decision is on the record next to the work.

The contrast: delivered, checked, not yet accepted

Handover bd7e5325 carries five steps, and its acceptance record reads five of five steps checked, status pending, release hint hold. Nothing about the work failed; the client simply has not decided yet, and the record keeps the two ideas separate: the delivery is verified, the acceptance is outstanding. Before you pay, you want to be looking at the first shape. The record is what lets you tell them apart at a glance.

What the check cannot tell you

  • Whether the work is good. A receipt proves the saved result of a call has not changed since it was saved. Quality, correctness, and taste remain your judgment, now made against the actual outputs instead of a paragraph about them.
  • Who the human behind the account is. The record covers the work: the calls, the results, the times. It does not prove the identity of the person operating the contractor's side, and this page will not pretend otherwise.
  • Anything about work done off the connection. Steps the contractor ran elsewhere were never recorded here. Their absence from the handover is visible, and what you do with that absence, ask, discount, or walk, is a buying decision the record informs but does not make.

Make the check the default, not the exception

The check is easiest when it was agreed before the work started. The contract page gives the clauses in copy-paste form: delivery defined as the handover link, acceptance defined as your recorded decision, payment released on acceptance. The payment-side companion is proof before payment: the order of operations that keeps the money behind the evidence. And the freelancer-side mirror of this page is the client who ghosted after delivery: same record, other side of the table.

Questions, answered

My contractor says the AI did the work. How do I check before I pay?

Ask for the record, then check it yourself. When AI work runs through Zambo, every call leaves a verifiable receipt at the moment it runs, and the delivery arrives as one handover link: the goal, the steps in order, each step with its own receipt and timestamp. Open the link and read the steps instead of the summary. Open two or three receipts and check that each saved result matches what the step claims. Then read the acceptance state: it stays pending until you accept, and your acceptance is itself recorded, with the release hint flipping to ok_to_release. Work with a record underneath it can be checked before money moves. Work that exists only as the contractor's summary cannot, and that difference is what you are pricing.

The contractor sent screenshots and a summary. Is that enough?

No. A screenshot is a picture of a claim, and a summary is written after the fact by the side being paid. Neither can be checked by anyone but the person who made it. A receipt is fixed at execution time and sits at a public link: you open it, anyone you forward it to opens the same record, and its saved result either recomputes against its commitment or it does not. Demand the form of evidence a stranger could check without your account, your permission, or the contractor's cooperation.

Does the record prove the work is good?

No, and a record that claimed to would be lying to you. A verifiable receipt proves that the saved result of a call has not changed since it was saved. Whether the result is good, correct, or worth the price is your judgment. The record changes what that judgment is made from: the actual saved outputs, step by step, with their sources states shown, instead of a confident paragraph about them. Check the two or three steps the payment turns on closely and skim the rest.

What if some steps have no receipt?

Then those steps are unverified, and the record says so by absence: a step that did not run through the connection has no receipt under it, and a source that was not checked reads not_checked rather than being smoothed over. Gaps staying visible is the point. Ask about each gap before you pay: work done elsewhere may be fine, but it is priced as a claim, not as checked work, and the acceptance decision is yours to make step by step.

What should I set up so the next hire is easy to check?

Put the record in the agreement before the work starts: delivery defined as the handover link, acceptance defined as your recorded decision, payment released on acceptance. The contract page on this hub gives the clauses in copy-paste form. On the Zambo side the setup is the same connection the work runs on. For $0.99, check the next delivery this way before any money moves: get the Day Pass. A Day Pass covers 24 hours, and ongoing use is the Zambo Pass at $29 a month or $290 a year, $19 a month for $ZAMBO holders. Checking one delivery the way this page describes takes minutes.

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