Whether a run answers a conversation's opening request, the only turn discovery asks about: its
messages hold exactly one user message. A follow-up turn carries the earlier requests in its
history (or the summary of them, which also arrives as a user message), and may be continuing work
with an agent already engaged, which a suggestion must not pull the agent away from. Assistant and
system messages do not count, so a greeting before the first request still leaves it the opening
turn. Read it from the messages the run started with, before the framework adds any.
Whether a run answers a conversation's opening request, the only turn discovery asks about: its messages hold exactly one user message. A follow-up turn carries the earlier requests in its history (or the summary of them, which also arrives as a user message), and may be continuing work with an agent already engaged, which a suggestion must not pull the agent away from. Assistant and system messages do not count, so a greeting before the first request still leaves it the opening turn. Read it from the messages the run started with, before the framework adds any.