Allow spawn_agent to explicitly select a configured custom agent

What variant of Codex are you using?

APP

What feature would you like to see?

Codex supports custom agents with their own model and reasoning settings, but the current spawn_agent tool only accepts task_name, message, and fork_turns, with no agent_name or agent_type parameter. In testing, the spawned session had agent_role = null and inherited the parent model instead of using the configured investigator agent. Is there a supported way to explicitly select a custom agent when spawning, or is this capability planned?

Additional information

_No response_