For a website that accepts a binding order or quote, an “I agree” checkbox is weak evidence if the customer can change quantity afterwards. Commission a review state tied to the exact submitted version, with a clear way to inspect and correct the details.
Primary evidence and claim boundaries
WCAG 3.3.4 addresses specified legal, financial and stored-data submissions through reversibility, checking or confirmation options. It does not prescribe a universal checkbox or define contract law. Primary reference · Read 18 October 2026.
Filled acceptance example
Original synthetic teaching scenario, not a client case, provider integration test or business result. The example policy needs the actual owner’s approval; scroll the table on narrow screens.
| Input and state | Declared check | Expected output and decision |
|---|---|---|
| Q18 revision1: 2 units atAUD50 | Review totalAUD100; confirm revision1 | Ready only for unchanged revision1 |
| Confirmed revision1 | Change quantity to 3; revision2 | Invalidate old confirmation; showAUD150 for review |
| Confirmation says revision1 | Submit payload revision2 | Reject mismatch; do not silently submit |
| User chooses Correct details | Return to editable draft | Preserve entries; do not create an order |
Practical handover procedure
- Identify whether the flow falls within the criterion and choose the intended prevention route with the responsible business reviewer. Describe the commitment in plain language.
- Attach the review to an immutable revision or payload digest. Replay confirm, edit, return and submit without making a real purchase.
- Have the server compare the submitted version and approved details. Retain synthetic evidence of rejected stale confirmations and the correction route.
Interpret the outcome
The originalAUD100 confirmation says nothing about the laterAUD150 payload. The useful output is a revision-linked decision, not an extra legal disclaimer. This acceptance contract can be assessed without sending a customer order, accepting terms or charging a payment method.
Acceptance decision
An edit after confirmation must require the chosen renewed review, or an explicitly supported alternative prevention route. Show the exact details the customer is approving.
Limits and unverified work
Synthetic quote arithmetic and interaction specification only. No legal-validity opinion, binding acceptance, order, payment or client data is created.
Download the filled bilingual acceptance record — Contains the inputs, steps, expectations and limits. This is a teaching record, not an executable production integration.