Kinsta's premium CDN powered by Cloudflare helps to maximize the performance of your site. With the cdn endpoint you can:
You can obtain the environment_id using the GET request with the WordPress Site Environments endpoint. 
The environment_id is also shown after the site_id in the URL in MyKinsta when you access the environment, for example in the URL https://my.kinsta.com/sites/details/fbab4927-e354-4044-b226-29ac0fbd20ca/c84ce214-69b9-4a32-8e67-880672cf1d38?idCompany=bdd25d71-5706-4890-870f-1adda17c505d:
site_id is fbab4927-e354-4044-b226-29ac0fbd20ca environment_id is c84ce214-69b9-4a32-8e67-880672cf1d38 company_id is bdd25d71-5706-4890-870f-1adda17c505dYou can obtain the cdn_cache_id using the GET request with the WordPress Site Environments endpoint.
The CDN endpoints may trigger longer tasks (from a few seconds to around a minute) on your environments. This is why they provide 202 Accepted response, with an operation_id in the body. To check the progress, you can use the /operations endpoint.
Clearing site CDN cache in progress
No or invalid API key provided to the request
Error occurred while trying to clear cache
{- "environment_id": "54fb80af-576c-4fdc-ba4f-b596c83f15a1",
 - "cdn_cache_id": "6ba7b810-9dad-11d1-80b4-00c04fd430c8"
 
}{- "operation_id": "cdn-cache:clear-54fb80af-576c-4fdc-ba4f-b596c83f15a1",
 - "message": "Clearing site CDN cache in progress",
 - "status": 202
 
}Updating Site Image Optimization in progress
No or invalid API key provided to the request
Error occurred while updating CDN Image Optimization
{- "environment_id": "54fb80af-576c-4fdc-ba4f-b596c83f15a1",
 - "image_optimization_type": "lossy"
 
}{- "operation_id": "cdn:update-image-optimization-54fb80af-576c-4fdc-ba4f-b596c83f15a1",
 - "message": "Updating Site Image Optimization in progress",
 - "status": 202
 
}