Update README.md

Author: ahx

README.md

@@ -56,11 +56,7 @@ Here is how to set it up:
     end
     ```
 2. Observe your application. You can do this in one of two ways:
-    - Inject a Module to wrap (prepend) the `call` method of your Rack app Class.
-      ```ruby
-      OpenapiFirst::Test.observe(MyApplication)
-      ```
-    - Or add an `app` method to your tests, which wraps your application with silent request / response validation. (✷1)
+    -  Add an `app` method to your tests, which wraps your application with silent request / response validation. (✷1)
       ```ruby
       RSpec.configure do |config|
         config.include OpenapiFirst::Test::Methods[MyApp], type: :request
@@ -73,6 +69,13 @@ Here is how to set it up:
         OpenapiFirst::Test.app(MyApp)
       end
       ```
+    - Inject a Module to wrap (prepend) the `call` method of your Rack app Class.
+      > [!IMPORTANT]  
+      > This is still work in progress. It works with basic Sinatra apps, but does not work with Hanami or Rails out of the box, yet. PRs welcome 🤗
+      
+      ```ruby
+      OpenapiFirst::Test.observe(MyApplication)
+      ```
 3. Run your tests. The Coverage feature will tell you about missing or invalid requests/responses.
 
 (✷1): It does not matter what method of openapi_first you use to validate requests/responses. Instead of using `OpenapiFirstTest.app` to wrap your application, you could also use the [middlewares](#rack-middlewares) or [test assertion method](#test-assertions), but you would have to do that for all requests/responses defined in your API description to make coverage work.