When a module completes without spawning a job — an empty branch, an
empty for-loop, or a module already marked Success — the flow hands
itself back through the UpdateFlow channel, and the result processor
resumed it with unrecoverable = true regardless of what sent it. That
flag means "the previous step's worker died", which holds for none of
the three producers except a suspend that ended without approval.
The stale argument was inert until continue_on_same_worker and
continue_with_runners started reading it, since when the step after such
a module is pushed as an ordinary queued job. It is then routed by tag
and can land on any worker in the pool, breaking both the ./shared
directory contract and the guarantee that a same_worker flow stays on a
worker able to run it — a step whose tag resolves to a worker group that
cannot execute its language fails instantly, taking the flow with it.
Carry the flag on the UpdateFlow message so each producer states its own
case, rather than having the shared receiver assume the worst. The three
that hand back a live flow forward whatever their caller reported, so a
genuinely unrecoverable failure still crosses the hop unchanged.
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
Ruben FiszelandClaude Opus 5
1aee22296e