L16 - Application & Domain Logic¶
L16 covers the product, workflow, domain rules, user experience, business process, and application-specific value created on top of the lower layers. It is the part users usually experience directly.
L16Application & Domain Logic
- Workflow
- Domain rules
- User experience
- Outcome ownership
What belongs here¶
L16 is where AI systems become products, copilots, agents, research workflows, internal tools, creative systems, or domain-specific applications. It is not less technical than lower layers; it simply asks different questions about usefulness, accountability, and fit.
Representative products and domains¶
| Product or domain | Why it might fit | Adjacent layers |
|---|---|---|
| ChatGPT | General AI assistant product built on model, tool, memory, and governance layers. | L8 context, L14 memory, L15 safety |
| Claude | Assistant product and API surface with model, tool, and safety behavior visible to users. | L10 tools, L15 safety |
| Microsoft Copilot | Product family embedding AI into productivity workflows. | L14 identity, L16 workflows |
| GitHub Copilot | Developer-assistance product with IDE, codebase, and workflow integration. | L9 retrieval, L10 tools |
| Cursor | AI coding environment where application UX and domain workflow are central. | L8 context, L10 tools |
| Perplexity | Answer and research product where retrieval, citations, and UX combine. | L9 retrieval, L16 product |
| Harvey | Domain-focused AI product for legal and professional services workflows. | L15 governance, L16 domain logic |
| Dollhouse Collection | Catalog and activation product where discovery, install flows, and artifact handling define the user experience. | L9 retrieval, L11 registry |
| Elemental Surveys | Applied research workflow where domain framing, review paths, and outcome ownership sit squarely in the application layer. | L8 context, L15 governance |
| Merview | Companion review and rendering utility that makes outputs, drafts, and artifact inspection usable to people. | L15 governance, L16 workflow |
| DollhouseMCP | User-facing runtime surface where many lower-layer capabilities become a coherent product and workflow. | L10 tools, L14 memory |
Boundary questions¶
- When does an agent framework remain L12 orchestration, and when does it become an L16 application?
- How should domain expertise, evaluation, and human review be represented without hiding lower-layer dependencies?
- Are "copilots" a product pattern, a domain pattern, or a bundle of many lower layers?
Signals to watch¶
- Domain-specific AI products developing their own evaluation and governance expectations.
- Application UX making lower-layer decisions visible through citations, approvals, memory controls, and tool traces.
- Organizations asking for stack-level transparency behind AI product behavior.