WCAG 2.2 HTML Fail and Pass Pairs: 64 Browser-Verified Cases Tested Against axe-core 4.14.0

64 hand-written pairs of HTML snippets covering 36 WCAG 2.2 success criteria. Each pair contains one version that fails a criterion and one corrected version that passes it. Every snippet was rendered and executed in headless Chromium against axe-core 4.14.0, and the raw engine output is stored with the data. Why the engine output matters. Public accessibility test corpora usually publish only the defective markup. This dataset records what an automated engine does with each snippet, including the cases where it stays silent. That makes it usable for scoring linters and LLM auditors against ground truth, and for measuring where automation actually stops. Measured results. axe-core 4.14.0 reported a violation on 39 of 64 defective documents (60.9%). The remaining 25 required scripted checks or manual review. 63 of 64 corrected documents produced no violation and no incomplete result. One corrected document returned an incomplete result that still needs human confirmation. Detection methods across the corpus: 37 axe-core rules, 3 axe-core plus manual review, 8 scripted custom checks, 16 manual-only criteria. Criteria with at least one defect in this corpus that axe-core flagged: 21 of 87. Across the full standard, 29 criteria have a mapped axe-core rule and 58 have none, so two thirds of WCAG 2.2 is out of reach for a scanner alone. Files. data/pairs.jsonl (fail markup, pass markup, explanation, manual test step, axe rule mapping), data/snippets.jsonl (flat snippet view), harness/run.mjs and harness/cases.mjs (Playwright plus axe-core runner, reproducible), harness/results.json (stored engine output for all 64 pairs). Reproduce. Install Playwright and axe-core 4.14.0, then run the harness against data/pairs.jsonl. Results should match harness/results.json aside from engine message wording. Part of the Veduis accessibility benchmark set. Maintained by Veduis LLC. Full-domain scanner built on these checks: vComplianceScanner. Demand letter triage workflow: ADA demand letter defense. Implementation manual: WCAG 2.2 developer guide. Company: veduis.com. Authoritative sources. W3C: Web Content Accessibility Guidelines (WCAG) 2.2 ADA.gov: Final rule on web and mobile app accessibility (28 CFR Part 35) Deque Systems: axe-core rule engine License. CC BY 4.0. Reuse with attribution to Veduis LLC.