diff --git a/README.md b/README.md
index 9f0bf3d0..bc32b433 100644
--- a/README.md
+++ b/README.md
@@ -627,33 +627,7 @@ POST http://localhost:1984/api/streams?dst=camera1&src=ffmpeg:http://example.com
 
 The HTTP API is the main part for interacting with the application. Default address: `http://localhost:1984/`.
 
-Interactive [OpenAPI](https://alexxit.github.io/go2rtc/api/).
-
-go2rtc has its own JS video player (`video-rtc.js`) with:
-
-- support technologies:
-   - WebRTC over UDP or TCP
-   - MSE or MP4 or MJPEG over WebSocket 
-- automatic selection best technology according on:
-   - codecs inside your stream
-   - current browser capabilities
-   - current network configuration
-- automatic stop stream while browser or page not active
-- automatic stop stream while player not inside page viewport
-- automatic reconnection
-
-Technology selection based on priorities:
-
-1. Video and Audio better than just Video
-2. H265 better than H264
-3. WebRTC better than MSE, than MP4, than MJPEG
-
-go2rtc has simple HTML page (`stream.html`) with support params in URL:
-
-- multiple streams on page `src=camera1&src=camera2...`
-- stream technology autoselection `mode=webrtc,webrtc/tcp,mse,hls,mp4,mjpeg`
-- stream technology comparison `src=camera1&mode=webrtc&mode=mse&mode=mp4`
-- player width setting in pixels `width=320px` or percents `width=50%`
+[API description](https://github.com/AlexxIT/go2rtc/tree/master/api).
 
 **Module config**
 
diff --git a/api/README.md b/api/README.md
new file mode 100644
index 00000000..76dc875b
--- /dev/null
+++ b/api/README.md
@@ -0,0 +1,117 @@
+# API
+
+Fill free to make any API design proposals.
+
+## HTTP API
+
+Interactive [OpenAPI](https://alexxit.github.io/go2rtc/api/).
+
+`www/stream.html` - universal viewer with support params in URL:
+
+- multiple streams on page `src=camera1&src=camera2...`
+- stream technology autoselection `mode=webrtc,webrtc/tcp,mse,hls,mp4,mjpeg`
+- stream technology comparison `src=camera1&mode=webrtc&mode=mse&mode=mp4`
+- player width setting in pixels `width=320px` or percents `width=50%`
+
+`www/webrtc.html` - WebRTC viewer with support two way audio and params in URL:
+
+- `media=video+audio` - simple viewer
+- `media=video+audio+microphone` - two way audio from camera
+- `media=camera+microphone` - stream from browser
+- `media=display+speaker` - stream from desktop
+
+## JavaScript API
+
+- You can write your viewer from the scratch
+- You can extend the built-in viewer - `www/video-rtc.js`
+- Check example - `www/video-stream.js`
+- Check example - https://github.com/AlexxIT/WebRTC
+
+`video-rtc.js` features:
+
+- support technologies:
+    - WebRTC over UDP or TCP
+    - MSE or HLS or MP4 or MJPEG over WebSocket
+- automatic selection best technology according on:
+    - codecs inside your stream
+    - current browser capabilities
+    - current network configuration
+- automatic stop stream while browser or page not active
+- automatic stop stream while player not inside page viewport
+- automatic reconnection
+
+Technology selection based on priorities:
+
+1. Video and Audio better than just Video
+2. H265 better than H264
+3. WebRTC better than MSE, than HLS, than MJPEG
+
+## WebSocket API
+
+Endpoint: `/api/ws`
+
+Query parameters:
+
+- `src` (required) - Stream name
+
+### WebRTC
+
+Request SDP:
+
+```json
+{"type":"webrtc/offer","value":"v=0\r\n..."}
+```
+
+Response SDP:
+
+```json
+{"type":"webrtc/answer","value":"v=0\r\n..."}
+```
+
+Request/response candidate:
+
+- empty value also allowed and optional
+
+```json
+{"type":"webrtc/candidate","value":"candidate:3277516026 1 udp 2130706431 192.168.1.123 54321 typ host"}
+```
+
+### MSE
+
+Request:
+
+- codecs list optional
+
+```json
+{"type":"mse","value":"avc1.640029,avc1.64002A,avc1.640033,hvc1.1.6.L153.B0,mp4a.40.2,mp4a.40.5,flac,opus"}
+```
+
+Response:
+
+```json
+{"type":"mse","value":"video/mp4; codecs=\"avc1.64001F,mp4a.40.2\""}
+```
+
+### HLS
+
+Request:
+
+```json
+{"type":"hls","value":"avc1.640029,avc1.64002A,avc1.640033,hvc1.1.6.L153.B0,mp4a.40.2,mp4a.40.5,flac"}
+```
+
+Response:
+
+- you MUST rewrite full HTTP path to `http://192.168.1.123:1984/api/hls/playlist.m3u8`
+
+```json
+{"type":"hls","value":"#EXTM3U\n#EXT-X-STREAM-INF:BANDWIDTH=1000000,CODECS=\"avc1.64001F,mp4a.40.2\"\nhls/playlist.m3u8?id=DvmHdd9w"}
+```
+
+### MJPEG
+
+Request/response:
+
+```json
+{"type":"mjpeg"}
+```