@dotey: Building an Agent Harness itself is no longer valuable—no matter how hard you try, you can't compete with model companies. Once the model upgrades, much of your work becomes obsolete. But building solutions on top of a mature Agent Harness has great potential. MCP only solves the connectivity problem, Skills only solves the domain knowledge problem…
Summary
The author argues that directly developing an Agent Harness is of little value because model companies will dominate, but building applications in vertical domains on top of mature frameworks still offers significant opportunities. It requires redesigning AI-native workflows, UI/UX, and data organization.
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Cached at: 05/25/26, 04:56 PM
Building an Agent Harness from scratch is no longer worthwhile — no matter how you do it, you can’t outpace the model companies. Every time a model is upgraded, a lot of the work becomes obsolete.
But building solutions on top of a mature Agent Harness? That’s where the real opportunity lies.
MCP only solves the connection problem. Skills only solve the domain knowledge problem.
There‘s still a lot to figure out in vertical domains:
- Redesigning old workflows to be AI-native Agent workflows.
- Redesigning UI/UX interactions for the Human-in-the-Loop part.
- Curating high-quality data for the vertical domain.
- And more.
These are things the model companies can’t do on their own — they need to be co-built.
Agents are the operating system of the future. A few model companies provide the models and the harness, and everyone else builds applications on top.
Wesley (@imwsl90): Just now someone in the group said the Agent thing is already over.
I basically agree.
Feels like there’s really nothing left to do in vertical Agents 🥶🥶🥶🥶
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