| name | improve-codebase-architecture |
| description | Find deepening opportunities in a codebase. Use when the user asks to "improve architecture", "find refactoring opportunities", "consolidate modules", "make code more testable", or wants the codebase made more AI-navigable. |
Improve Codebase Architecture
Surface architectural friction and propose deepening opportunities, refactors that turn shallow modules into deep ones. The aim is testability and AI-navigability.
Glossary
Use these terms exactly in every suggestion. Consistent language is the point, don't drift into "component," "service," "API," or "boundary." Full definitions in LANGUAGE.md.
- Module, anything with an interface and an implementation (function, class, package, slice).
- Interface, everything a caller must know to use the module: types, invariants, error modes, ordering, config. Not just the type signature.
- Implementation, the code inside.
- Depth, leverage at the interface: a lot of behaviour behind a small interface. Deep = high leverage. Shallow = interface nearly as complex as the implementation.
- Seam, where an interface lives; a place behaviour can be altered without editing in place. (Use this, not "boundary.")
- Adapter, a concrete thing satisfying an interface at a seam.
- Leverage, what callers get from depth.
- Locality, what maintainers get from depth: change, bugs, knowledge concentrated in one place.
Key principles (see LANGUAGE.md for the full list):
- Deletion test: imagine deleting the module. If complexity vanishes, it was a pass-through. If complexity reappears across N callers, it was earning its keep.
