Update index.mdx (#21861)

* Update index.mdx

add note that REST API usage not yet reflected in dashboard

* Update src/content/docs/browser-rendering/rest-api/index.mdx

---------

Co-authored-by: Kody Jackson <[email protected]>

Author: kathayl

src/content/docs/browser-rendering/rest-api/index.mdx

@@ -19,3 +19,9 @@ Use the REST API when you need a fast, simple way to perform common browser task
 Before you begin, make sure you [create a custom API Token](/fundamentals/api/get-started/create-token/) with the following permissions:
 
 - `Browser Rendering - Edit`
+
+:::note[Note]
+
+Currently, the Cloudflare dashboard displays usage metrics exclusively for the [Workers Binding API method](/browser-rendering/workers-binding-api/). Usage data for the REST API is not yet available in the dashboard. We are actively working on adding REST API usage metrics to the dashboard.
+
+:::