# Content freshness

Canonical HTML: /atlas/content-freshness
Atlas version: atlas-2026-07-28-v1
Category: Quality, provenance, and observability

## Definition

Content freshness describes when meaningful facts were last reviewed or changed.

## How it works

Accurate page versions, content hashes, Last-Modified values, and sitemap lastmod dates let recrawlers distinguish real updates from cosmetic deployments.

## How to validate it

Hash normalized content, record the editorial update separately from deployment time, and submit only materially changed canonical URLs.

## Common failure

Resetting every date on every deploy creates a false freshness signal and consumes crawl quota without adding information.

## Related topics

- [Conditional requests](/atlas/conditional-requests)
- [Source provenance](/atlas/provenance)