A session is a conversation container for an agent. Sessions have:
- A beginning (when the agent is started).
- An end (when the session is closed or expires).
- A transcript (the running record of what was said and done).
New sessions do not inherit the previous session's memory automatically — that's what long-term memory and the context-assembly step are for.
A sub-agent is a child session spawned by another agent to handle a specific task. The child runs in its own session, does its work, and returns a result to the parent. The parent's session is unaffected.