Master's reconstructable-requests overhaul (#179) meets the workflow tool:
- subagent-inprocess structured-output nudge becomes a system-prompt section
plus logged context (the injected-request waterfall shape is gone upstream)
- snapshot fixtures re-recorded on the merged tree so every request/header
carries the workflow tool; authored error-finish/cancel headers patched to
the merged tool list and system text
- architecture.md condensed back under its word ceiling; module graph regenerated