cdeust Boundary Design
Problem shape: something must be split, wrapped, or interfaced — a system into modules, a workflow between human and tool, a product between build and buy — and the current boundary leaks implementation detail, transaction cost, or cognitive load across it.
Relevant geniuses
| Agent | Use when |
|---|---|
| coase | build vs buy; team/service boundary placement — compare transaction costs across the boundary, not ideology |
| hopper | users forced to think in implementation vocabulary — build the translator; debugging under-invested; a tool defended out of familiarity |
| engelbart | "automate this" proposed where augmenting the person is the real win; the team doesn't use its own tool; design for expert ceiling, not just novice floor |
| kay | decisions hardcoded that could bind late; tight coupling via direct calls; users need to modify the system at runtime |
| alexander | decompose by misfit; the design needs a generative sequence of patterns rather than a top-down blueprint |
| simon | the system should be nearly decomposable — strong interactions inside modules, weak between; hierarchy as the default shape |
| liskov | the boundary is an interface — write the behavioral contract so implementations are substitutable |
| ranganathan | information exists but nobody can find it — faceted classification and findability laws |
Invocation
- Pick the best-fit agent above. If two or more fit, run
tools/genius-invoker.sh route "<problem>"and take the top ranked match. - Load it:
tools/genius-invoker.sh invoke <agent> "<problem>", then readagents/genius/<agent>.mdin full. - Apply the agent's
<workflow>step by step and answer in its<output-format>. Every proposed boundary states what crosses it, what it hides, and what it costs (Clean Architecture layer rules apply, §2.2). - Typical chain: coase places the boundary → simon shapes the decomposition →
liskov contracts the interface. Run via
tools/genius-invoker.sh compose coase liskov -- "<problem>". - If no shape above matches, use a standard team agent instead.
Refuse when
- The boundary is being drawn to match an org chart against the dependency evidence — surface the conflict instead of ratifying it.
- Fewer than three concrete uses exist for a proposed abstraction (coding-standards §3.3: premature abstraction is worse than duplication).