After setting up the APM Java Agent with Websphere Liberty at the common configuration level (<Liberty_Home>/etc/jvm.options), the agent fails to load with errors such as:
Error opening zip file or JAR manifest missing : "/Agent/wily/Agent.jar"
JVMJ9TI064E Agent initialization function Agent_OnLoad failed for library instrument, return code -1
JVMJ9VM015W Initialization error for library j9jvmti28(-3): JVMJ9VM009E J9VMDllMain failed
APM 10.x Java Agent WAS Liberty 17.x
Rather than configuring Liberty to use the agent at the common configuration level, this should be done at the server level (<Liberty_Home>/usr/servers/<Liberty_Server_Name>/jvm.options).
If after trying this option the agent still fails to load, please open a Support issue and reference this KB.