A story-driven, hands-on report about taking an existing open-source LangGraph.js agent, wrapping it in GraphOS, and learning what observability actually feels like when an agent goes sideways. There is a moment every agent project eventually reaches. The demo works. The graph looks clean. The tools are wired up. The prompt feels smart. And then one run goes sideways. Not in a dramatic, movie-scene way. In the real way. The assistant calls the same tool again. Then again. The state grows. The trace gets noisier. The budget keeps moving in one direction. And the hardest part is not even the cost. It is the feeling that you can no longer see the system clearly. That is the moment GraphOS was built for. This post is not just a feature announcement. It is a field report.…