| Layer | A distinct analytical view of the codebase (8 total) |
| Structural layer | Layers analyzing static code structure (1, 2, 3, 4, 7) |
| Behavioral layer | Layers analyzing runtime behavior and data flow (5, 6, 8) |
| Manifest | Canonical file list built from git ls-files (Layer 0 foundation) |
| Coverage | Percentage of manifest files analyzed by a layer |
| Afferent coupling (Ca) | Number of packages that depend on this package |
| Efferent coupling (Ce) | Number of packages this package depends on |
| Instability | Ce / (Ca + Ce). 0 = maximally stable, 1 = maximally unstable |
| Dead code | Definitions not exported, not imported, not called internally (conservative) |
| Entry point | CLI command, HTTP route, or hook that starts a user journey |
| Journey | Trace from entry point through call graph to outcome (depth-limited) |
| Outcome | Terminal action: file I/O, database op, subprocess, network call, or return |
| Cross-layer check | Validation that data is consistent across multiple layers |
| Transformation point | Function that both reads and writes data (data flow bridge) |