Documents how Workers interact with Cache Rules (#21614)

Author: angelampcosta

src/content/docs/cache/interaction-cloudflare-products/r2.mdx

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 pcx_content_type: how-to
 title: Enable cache in an R2 bucket
 sidebar:
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+  order: 3
 head:
   - tag: title
     content: Enable cache in an R2 bucket

src/content/docs/cache/interaction-cloudflare-products/waf-snippets.mdx

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 pcx_content_type: how-to
 title: Control cache access with WAF and Snippets
 sidebar:
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   - tag: title
     content: Control cache access with WAF and Snippets

src/content/docs/cache/interaction-cloudflare-products/workers-cache-rules.mdx

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+---
+pcx_content_type: how-to
+title: How Workers interact with Cache Rules
+sidebar:
+  order: 2
+head:
+  - tag: title
+    content: How Workers interact with Cache Rules
+
+---
+
+Your Workers script can override [cache rule](/cache/how-to/cache-rules/) behavior, whether it is applied to a zone using Cloudflare or a zone that is not proxied through Cloudflare.
+
+For example, if there is a cache rule configured to bypass cache for `example.com/foo`, but your Workers script sets `cacheEverything: true`, the script's setting will take precedence, and the request will be cached. The same applies if the request is made to a non-Cloudflare zone — the Worker's `cacheEverything` setting will still override.
+
+## Precedence order
+
+Cache behavior is determined by the following order of precedence:
+
+1. Workers script settings
+2. Cache rules
+3. Page rules
+
+Cache rules override page rule settings, and Workers scripts override cache rules. Among rules at the same level, the one with the highest specificity takes priority.
+
+## Compatibility flags
+
+This override behavior is controlled by [compatibility flags](/workers/configuration/compatibility-flags/):
+
+- For the Fetch API: `request_cf_overrides_cache_rules`
+- For the Cache API: `cache_api_request_cf_overrides_cache_rules`
+
+These flags must be enabled to allow Workers scripts to override cache rules.
+
+If your Worker has a compatibility date of 2025-04-02 or earlier, these flags are not enabled by default. In that case, cache settings defined in the Worker will not override existing cache rules.
+
+### Example (Older compatibility date)
+
+If a cache rule is configured to bypass cache for `example.com/foo`, and a Worker with a compatibility date of `2025-04-02` or earlier tries to set `cacheEverything: true`, the cache rule will take effect — and the response will not be cached.