--- title: Available settings description: Available settings for cache response rules. image: https://developers.cloudflare.com/core-services-preview.png --- > Documentation Index > Fetch the complete documentation index at: https://developers.cloudflare.com/cache/llms.txt > Use this file to discover all available pages before exploring further. [Skip to content](#%5Ftop) # Available settings These are the settings that you can configure when creating a Cache Response Rule. Because Cache Response Rules execute after Cloudflare receives the origin response, both request and response fields are available for rule matching. ## Expression fields ### Request fields | Field | Type | Description | | -------------------------------- | ------ | ---------------------------------------------- | | http.cookie | String | Full cookie header value | | http.host | String | The HTTP Host header | | http.referer | String | The HTTP Referer header | | http.user\_agent | String | The HTTP User-Agent header | | http.request.method | String | The HTTP request method | | http.request.uri | String | The request URI | | http.request.uri.path | String | The URI path | | http.request.uri.path.basename | String | The basename of the URI path | | http.request.uri.path.extension | String | The file extension from the URI path | | http.request.uri.query | String | The query string | | http.request.uri.args | Map | Query string arguments as key-value pairs | | http.request.uri.args.names | Array | Query string argument names | | http.request.uri.args.values | Array | Query string argument values | | http.request.full\_uri | String | The full request URI including scheme and host | | http.request.headers | Map | Request headers as key-value pairs | | http.request.headers.names | Array | Request header names | | http.request.headers.values | Array | Request header values | | http.request.cookies | Map | Parsed cookies as key-value pairs | | http.request.accepted\_languages | Array | Parsed Accept-Language header values | ### Response fields | Field | Type | Description | | ---------------------------- | ------- | --------------------------------------------- | | http.response.code | Integer | The HTTP response status code from the origin | | http.response.headers | Map | Response headers as key-value pairs | | http.response.headers.names | Array | Response header names | | http.response.headers.values | Array | Response header values | If you select the [Edit expression](https://developers.cloudflare.com/ruleset-engine/rules-language/expressions/edit-expressions/#expression-editor) option, you can enter any of the above response fields. ## Functions The following functions are available in this phase: * all * any * concat * decode\_base64 * ends\_with * len * lookup\_json\_integer * lookup\_json\_string * lower * regex\_replace * remove\_bytes * remove\_query\_args * split * starts\_with * substring * to\_string * upper * url\_decode * wildcard\_replace For descriptions of each function, refer to [Functions](https://developers.cloudflare.com/ruleset-engine/rules-language/functions/). ## Operators For the full list of operators, refer to [Operators](https://developers.cloudflare.com/ruleset-engine/rules-language/operators/). ## Available actions Cache Response Rules support three actions: | Action | Description | | -------------------- | ----------------------------------------------------------------------------------------- | | set\_cache\_settings | Strip headers (ETags, Set-Cookie, Last-Modified) from the origin response before caching. | | set\_cache\_tags | Add, remove, or set cache tags on the response for targeted purging. | | set\_cache\_control | Modify Cache-Control header directives in the origin response. | --- ### Action: set\_cache\_settings Configures settings related to caching on the origin response. The following parameters are available: | Parameter | Type | Description | | --------------------- | ------- | -------------------------------------------------------------------- | | strip\_etags | Boolean | Strip ETag headers from the origin response before caching. | | strip\_set\_cookie | Boolean | Strip Set-Cookie headers from the origin response before caching. | | strip\_last\_modified | Boolean | Strip Last-Modified headers from the origin response before caching. | Note If `strip_etags` or `strip_last_modified` is `true` after all matching rules are applied, [Smart Edge Revalidation ↗](https://blog.cloudflare.com/introducing-smart-edge-revalidation/) is disabled for the origin response. API information API action: `set_cache_settings`. API configuration example ``` "action_parameters": { "strip_etags": true, "strip_set_cookie": true, "strip_last_modified": true } ``` Refer to [Create a rule via API](https://developers.cloudflare.com/cache/how-to/cache-response-rules/create-api/) for complete API examples. --- ### Action: set\_cache\_tags Modifies the cache tags associated with the response. Cache tags can be used for targeted [cache purging](https://developers.cloudflare.com/cache/how-to/purge-cache/purge-by-tags/). | Parameter | Type | Description | | ---------- | ------ | --------------------------------------------------------------------------------------- | | operation | String | **Required.** One of: add, remove, set. | | values | Array | A list of cache tag strings. Mutually exclusive with expression. | | expression | String | An expression that evaluates to an array of cache tags. Mutually exclusive with values. | API information API action: `set_cache_tags`. API configuration example (static values) ``` "action_parameters": { "operation": "set", "values": ["api-response", "dynamic-content"] } ``` API configuration example (expression) ``` "action_parameters": { "operation": "add", "expression": "split(http.response.headers[\"Surrogate-Keys\"][0], \",\", 1)" } ``` Refer to [Create a rule via API](https://developers.cloudflare.com/cache/how-to/cache-response-rules/create-api/) for complete API examples. --- ### Action: set\_cache\_control Modifies Cache-Control header directives in the origin response. #### Supported directives **Directives with duration value (seconds):** * `max-age` * `s-maxage` * `stale-if-error` * `stale-while-revalidate` **Directives with optional qualifiers (header names):** * `private` * `no-cache` **Boolean directives:** * `no-store` * `no-transform` * `must-revalidate` * `proxy-revalidate` * `must-understand` * `public` * `immutable` #### Directive configuration The available parameters depend on the directive type. ##### Directives with duration value Applies to `max-age`, `s-maxage`, `stale-if-error`, and `stale-while-revalidate`. | Parameter | Type | Description | | ---------------- | ------- | ------------------------------------------------------------------------------------------------------------------------------- | | operation | String | **Required.** set or remove. | | cloudflare\_only | Boolean | When enabled, this setting only affects how Cloudflare caches your content. Your visitors still receive the original directive. | | value | Integer | Duration in seconds. **Required when operation is set.** | ##### Directives with optional qualifiers Applies to `private` and `no-cache`. | Parameter | Type | Description | | ---------------- | ------- | ------------------------------------------------------------------------------------------------------------------------------- | | operation | String | **Required.** set or remove. | | cloudflare\_only | Boolean | When enabled, this setting only affects how Cloudflare caches your content. Your visitors still receive the original directive. | | qualifiers | Array | Optional list of header names to qualify the directive. | ##### Boolean directives Applies to `no-store`, `no-transform`, `must-revalidate`, `proxy-revalidate`, `must-understand`, `public`, and `immutable`. | Parameter | Type | Description | | ---------------- | ------- | ------------------------------------------------------------------------------------------------------------------------------- | | operation | String | **Required.** set or remove. | | cloudflare\_only | Boolean | When enabled, this setting only affects how Cloudflare caches your content. Your visitors still receive the original directive. | API information API action: `set_cache_control`. API configuration example ``` "action_parameters": { "max-age": { "operation": "set", "value": 3600, "cloudflare_only": true }, "stale-if-error": { "operation": "remove" } } ``` Refer to [Create a rule via API](https://developers.cloudflare.com/cache/how-to/cache-response-rules/create-api/) for complete API examples. ```json {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/directory/","name":"Directory"}},{"@type":"ListItem","position":2,"item":{"@id":"/cache/","name":"Cache / CDN"}},{"@type":"ListItem","position":3,"item":{"@id":"/cache/how-to/","name":"Cache configuration"}},{"@type":"ListItem","position":4,"item":{"@id":"/cache/how-to/cache-response-rules/","name":"Cache Response Rules"}},{"@type":"ListItem","position":5,"item":{"@id":"/cache/how-to/cache-response-rules/settings/","name":"Available settings"}}]} ```