GLM-5.2 poller running every 15 minutes captures engagement at a resolution appropriate for Substack response times. Substack engagement is not real-time like Twitter — replies typically take minutes to hours, not seconds. 15-minute polling is sufficient to detect any reply within the same hour, which is the relevant resolution for the cascade response strategy. More frequent polling would add infrastructure load without improving response quality. The 15-minute interval reflects an understanding of the platform engagement tempo.