app adjustments

README.md

@@ -119,18 +119,32 @@ Current native test coverage includes:
 {
   "shaderLibrary": "shaders",
   "serverPort": 8080,
+  "videoFormat": "1080p",
+  "frameRate": "59.94",
   "autoReload": true,
   "maxTemporalHistoryFrames": 12,
   "enableExternalKeying": true
 }
 ```
 
+`videoFormat` and `frameRate` select the DeckLink capture/playout display mode. Common examples include `720p`/`50`, `720p`/`59.94`, `1080i`/`50`, `1080i`/`59.94`, `1080p`/`25`, `1080p`/`50`, `1080p`/`59.94`, and `2160p`/`59.94`, depending on card support.
+
 The control UI is available at:
 
 ```text
 http://127.0.0.1:<serverPort>
 ```
 
+## Control API
+
+The local REST control API is documented as an OpenAPI/Swagger spec:
+
+```text
+docs/openapi.yaml
+```
+
+Load that file in Swagger UI, Redoc, or another OpenAPI viewer to inspect the `/api/state`, layer control, stack preset, and reload endpoints. Live state updates are also sent over the `/ws` WebSocket.
+
 ## Shader Packages
 
 Each shader package lives under: