How to Test Your Agents on Real Tasks With Harbor - Xander Song, Arize AI

Xander Song, an engineer at Arize AI who works on Phoenix, introduces Harbor, an open source framework for evaluating agents on realistic tasks with real data in isolated sandboxes. He explains tasks, Docker environments, verifiers and rewards, trials and jobs, oracles that validate your setup before you spend tokens, and ATIF trajectories. Then he shows how his team runs Harbor at scale on Daytona and with Phoenix to test a prompt change that steered agents toward a new SQL tool, cutting tool calls without hurting correctness. Chapters 00:00 Intro: shipping on evidence, not vibes 01:28 What H