diff --git a/src/azure-cli/azure/cli/command_modules/appservice/_help.py b/src/azure-cli/azure/cli/command_modules/appservice/_help.py
index ef939e6fb22..84256673c7f 100644
--- a/src/azure-cli/azure/cli/command_modules/appservice/_help.py
+++ b/src/azure-cli/azure/cli/command_modules/appservice/_help.py
@@ -1818,7 +1818,7 @@
 
 helps['webapp list-runtimes'] = """
 type: command
-short-summary: List available built-in stacks which can be used for web apps.
+short-summary: List available built-in stacks which can be used for web apps. The Canonicalized web runtime should be used in the format of Framework|Version, e.g. "PHP|5.6".
 """
 
 helps['functionapp list-runtimes'] = """