doc update

Author: morisil

README.md

@@ -1,4 +1,7 @@
 # xemantic-ai-file-magic
 Detecting file content type before submitting binary content to LLM, a small Kotlin multiplatform library.
 
-> [!NOTICE] documentation will follow
+> [!TIP]
+> documentation will follow
+
+It is being used by [anthropic-sdk-kotlin](https://github.com/xemantic/anthropic-sdk-kotlin).