In this week’s The Insider newsletter, managing editor Gretchen Gavett writes on agentic AI, thriving under a new boss, and catastrophizing. First, she highlights an argument about how Agentic AI is reshaping the way startups form and compete, offering speed, capital efficiency, and customer learning. Then, she discusses executive coach Dina Denham Smith’s playbook for thriving under a new boss and deliberately shaping how you’re seen. The newsletter closes on an IdeaCast episode on rumination that explains how breaking free of negative thought spirals restores focus and reduces reactivity.