The DEBUG action-logging reducer ran debugCaseOutput (Mirror reflection plus type-name demangling), snapshotted the entire app state, and deep- compared it on every single action. Stack sampling of an idle build with 24 terminal surfaces attributed a steady ~5% of the main thread to this path, with 93% of all reducer time on the main thread spent in the logging wrapper rather than the reducers themselves. Gate the whole block behind PROWL_LOG_TCA_ACTIONS (default off) so a normal Debug run pays none of it. When enabled, route the action label through SupaLogger.notice -> the unified log instead of print, so the stream is visible via 'make log-stream'; the Debug SupaLogger.debug prints to a stdout that a Finder/launchd-launched app discards. Add SupaLogger.notice (unified log in all configs) and LogActionsReducer pass-through tests. Document the flag in AGENTS.md. The markdown hook added blank lines before two pre-existing code fences in AGENTS.md.