agentDisplayName is optional in the CLI hook payload (it may be absent for some subagents). The field list currently reads as if it’s always present; update the description to mark it as optional and consider noting what to expect when it isn’t provided.

agentDisplayName is optional in the CLI hook payload (it may be absent for some subagents). The field list currently reads as if it’s always present; update the description to mark it as optional and consider noting what to expect when it isn’t provided. #8914