The case for running product delivery on Claude-native tools, a proprietary MCP layer, and Asana as the canonical spine — rather than building another in-house platform in the age of generative AI.
The logic that built the SaaS industry — buy the commodity, own your differentiation — has been abandoned by the same leaders who sold it. Generative AI has not changed the principle. It has sharpened it.
The strongest case for Option A is codebase depth and compliance control. For FieldAssist-scale companies that have already built a proprietary codebase MCP, this argument collapses — the depth is already owned, and compliance is owned at the MCP layer rather than the UI layer. The second argument is vendor lock-in with Claude. Real, but manageable — model routing through MCP gives you a swap path, and the lock-in is shallower than the migration cost of leaving a built platform. The third is branded client experience. Valid only if you sell the platform; otherwise, clients care about delivery speed and output quality, neither of which improves with a custom UI.
Net verdict — Option B wins on every dimension that compounds, and ties or loses only on dimensions that are fixed-cost. The gap widens with every Claude release.
The discipline that makes this work is refusing to let layers bleed into each other. Execution runs in Claude. Work runs in Asana. Knowledge lives in Drive. Differentiation lives in your MCP.
Every step below is one of three things. The discipline is that it stays one thing. Humans never draft what agents can draft. Agents never approve what humans must approve. Automation never decides anything.
Interactive work happens on laptops. Autonomous work runs on a Cloudflare Worker. Build both from day one — the second is what makes the system continue working while the team is asleep.
The architecture is designed for graceful evolution. Start thin, prove the pattern, expand the envelope. Every capability that foundation models absorb over time thins your seam further — which is the goal, not a risk.
Every failure of this architecture traces back to one of these four being violated. They are non-negotiable regardless of team size, client pressure, or vendor change.