# Product identity and canonical URL

> Whether each product has one stable canonical URL matching the feed link plus real manufacturer identifiers, so an agent can match your item to the same product across competing stores.

<!-- Canonical: https://agentmint.net/signals/product-identity/ · Signal in the AgentMint.net Signals Database · Evidence: spec-fact (Very high confidence) · Last verified 2026-07-08 · Evidence types are load-bearing: spec-fact | reported | hypothesis (no measured). -->

- **Affects (funnel stage):** Matching
- **Evidence:** spec-fact
- **Confidence:** Very high
- **Impact:** 2/3
- **Status:** active
- **Last verified:** 2026-07-08

## Per-platform status

Undocumented platforms show "unknown" - honest unknowns, never invented.

| Platform | Status | Notes | Source |
| --- | --- | --- | --- |
| ChatGPT | unknown | Not documented by this platform. | - |
| Gemini / Google AI Mode | unknown | Not documented by this platform. | - |
| Perplexity | unknown | Not documented by this platform. | - |
| Copilot | unknown | Not documented by this platform. | - |
| Claude | unknown | Not documented by this platform. | - |

## Evidence and sources

- [Merchant listing structured data](https://developers.google.com/search/docs/appearance/structured-data/merchant-listing) (2026-07-08)
- [Product data specification](https://support.google.com/merchants/answer/7052112) (2026-07-08)

## How to act on this

Give each product one canonical URL that resolves to the purchasable page and matches the feed link, and populate gtin/brand/mpn wherever a real identifier exists (never invent one).

### Related checklist items
- [Give each product one clean, stable, canonical URL.](https://agentmint.net/tools/agentic-readiness-checklist/#a-bot-access-06) (Readiness)
- [Include product identifiers (gtin*, brand, and mpn) where they exist.](https://agentmint.net/tools/agentic-readiness-checklist/#a-structured-data-03) (Readiness)

### Handbook chapters
- [Information Density: Facts Per Token on Machine Surfaces](https://agentmint.net/handbook/information-density/)

### Related signals
- [Offer markup completeness and truthfulness](https://agentmint.net/signals/offer-markup-completeness/)
- [Validation hygiene (use existing validators)](https://agentmint.net/signals/validation-hygiene/)