Update README.md

Author: smalinin

README.md

@@ -1,5 +1,5 @@
 # WebLLM-Tools-Sample
-Sample of using tools with WebLLM
+Sample of using tools with WebLLM (Note it works only in browsers with WebGPU support and you must have at last 4Gb of free VRAM)
 
 [Demo App](https://openlinksoftware.github.io/WebLLM-Tools-Sample/src/index.html)