Vendor-Extensions.md

@@ -125,6 +125,15 @@ definitions:
 
 For assigning field numbers: https://developers.google.com/protocol-buffers/docs/proto3#assigning_field_numbers
 
+### PowerShell
+#### x-powershell-method-name
+
+To customize the method name in the PowerShell client, e.g.
+```
+x-powershell-method-name: Invoke-CustomMethod
+```
+
+
 ### Swift
 #### x-swift-hastable