James had been staring at TutorClaw's $60/month infrastructure cost and its $15,750/month revenue. The margin was extraordinary. But something nagged him.
"We designed Architecture 4 in Module 9.3," he said. "But you mentioned there were three other ways to build this. Were they all this cheap?"
Emma shook her head. "Not even close. Let me show you the full picture."
You are doing exactly what James is doing. You have one architecture's numbers memorized. Now you need to see all four side by side to understand why Architecture 4 was the right choice.
Here are all four architectures evaluated across eight dimensions, using TutorClaw's real numbers at 16,000 learners:
Architecture 4's margin of 99.5% is not an incremental improvement; it is a fundamentally different business model. While Stripe fees (~$1,650/mo) will drop this gross margin to ~89% in practice, the structural advantage remains overwhelming compared to the 22% of Architecture 1.
The LLM inference cost is the story. Architectures 1, 2, and 3 all carry a ~$12,000/month liability because the operator pays for every learner's tokens. Architecture 4 shifts that cost entirely: the learner chooses their model and pays their own provider.
Infrastructure costs also vary. NanoClaw (Architecture 2) runs isolated containers for each learner, pushing infra to nearly $1,600/month. Architecture 4's MCP server and serverless database cost barely $70/month total, and that cost stays flat whether you serve 1,000 or 100,000 learners.
Cost is not the only dimension. Choose your architecture based on your product needs:
Architecture 4 dominates on every dimension except one: it requires learners to have OpenClaw installed.
For learners outside the ecosystem, a lightweight Architecture 1 instance ("TutorClaw Web") serves as the temporary onramp. For a public product, you would need both: Architecture 4 as the primary premium experience and a minimal Architecture 1 fallback for new users.
James leaned back. "This is like evaluating shipping contracts. One carrier looks cheap per package but has a fuel surcharge that doubles the cost at volume. LLM is that surcharge. Twelve thousand dollars a month, hiding in the quotes for Architectures 1 through 3. Architecture 4 just removes it entirely."
Emma nodded. "The ingredients are delivered for free by the user's own model. That is what Module 9.4, Chapter 6 covers."