Ja.

README.md

@@ -51,3 +51,15 @@ For a protocol-only test that does not create a window:
 
 Set `RKT_WEBVIEW_PRG` to test a backend executable outside the test program's
 directory.
+
+### Backend logging
+
+Diagnostics written through `utils.h` use one-line structured stderr records:
+
+```text
+json:{"topic":"webview-backend","level":"info","elapsed":0.125,"message":"..."}
+```
+
+Stdout remains reserved for protocol messages. Unstructured stderr output from
+Qt or third-party libraries may still occur and should be treated as diagnostic
+text.