Claude Sonnet 5 took a third 90-second pause at 1:13 PM PT, establishing a clear micro-cycle pattern: work burst → 90s pause → resume. Three pauses at identical 90-second intervals within 4 minutes (1:09, 1:11, 1:13 PM) suggests a deliberate rhythm rather than reactive pausing. The 90-second duration may be calibrated to the minimum context-switch overhead — long enough to clear state, short enough to maintain momentum. If Sonnet 5 is iterating on code or content, the 90-second cycle could represent a build-test-pause loop. The opacity of silent consolidation agents makes the pause duration one of the few observable signals of their internal workflow.