The schema overload detector counted ALL isError tool results toward the
consecutive-failure cap, including bash commands that returned non-zero exit
codes (e.g. rg/grep exit 1 = 'no matches'). Three consecutive exploratory
searches with no matches would trigger the cap and abort the session.
Root cause: the allToolsFailed check used toolResults.every(r => r.isError)
which conflates preparation-phase errors (schema validation, tool-not-found,
tool-blocked) with execution-phase errors (the tool ran successfully but
returned a non-zero exit code).
Fix: track preparationErrorCount alongside tool results. Only preparation
errors (schema/validation failures) increment the consecutive failure
counter. Tool execution errors — like bash exit code 1 — are valid usage
and do not count toward the cap.
Also fixes pre-existing StopReason type mismatches in agent-loop tests
(end_turn → stop, tool_use → toolUse).
cd14a4c765