Signal
Validation hygiene (use existing validators)
Whether structured data, feeds, and protocol manifests are run through existing maintained validators rather than a homegrown checker.
Per-platform status
Where a platform documents relevant behavior, its status and source are shown. Undocumented platforms show "unknown" - honest unknowns, never invented.
| Platform | Status | Notes | Source |
|---|---|---|---|
| ChatGPT | Unknown | Not documented by this platform. | - |
| Gemini / Google AI Mode | Supported | Google names the Rich Results Test for validating structured data during development, and the rich result status reports after deployment. | Source (opens in new tab) · verified 2025-12-10 |
| Perplexity | Unknown | Not documented by this platform. | - |
| Copilot | Partial | The Content API returns validation errors and warnings on insert, including missing identifiers, and offers a dry-run test mode. | Source (opens in new tab) · verified 2026-01-02 |
| Claude | Unknown | Not documented by this platform. | - |
Evidence and sources
This signal is typed spec-fact (Very high confidence).
- Merchant listing structured data (opens in new tab) · 2026-07-08
- ucptools.dev: UCP/ACP validator (opens in new tab) · 2026-07-08
How to act on this
Run the Rich Results Test, Schema.org validator, Merchant Center diagnostics, and a maintained UCP/ACP validator on every deploy; fix every error, then triage warnings.
Related checklist items
Handbook chapters