diff --git a/basyx.aasenvironment/Readme.md b/basyx.aasenvironment/Readme.md
index 96fd375af..d1f6a1286 100644
--- a/basyx.aasenvironment/Readme.md
+++ b/basyx.aasenvironment/Readme.md
@@ -40,9 +40,12 @@ For examples, see [application.properties](./basyx.aasenvironment.component/src/
 
 ## AAS Environment Upload Endpoint
 
-AAS environments (e.g. XML, JSON, AASX) can be uploaded to the `/upload` endpoint. 
+AAS environments (e.g. XML, JSON, AASX) can be uploaded by a multipart/form-data POST on the `/upload` endpoint. Please note that the following MIME types are expected for the respective file uploads:
+* AASX: application/asset-administration-shell-package
+* JSON: application/json
+* XML: application/xml
     
 The upload follows the same rules as the preconfiguration in terms of handling existing AAS, submodels and concept descriptions. In order for the file to be recognized correctly, please make sure that its MIME type is properly configured.
 
 ## AAS Environment Features
-* [AAS Environment Authorization](basyx.aasenvironment-feature-authorization)
\ No newline at end of file
+* [AAS Environment Authorization](basyx.aasenvironment-feature-authorization)