- stdlib only. No dependencies, ever, in the adapter path — adapters must stay copy-portable into other projects that vendor single files.
- Adapters own all vendor knowledge. Adding an agent in an existing family is a config entry plus a matrix row; no consumer changes.
- Ownership-marked wiring. Install is idempotent and uninstall is surgical: your own hooks in the same config are never touched.
- The matrix carries provenance. Every row records the version and date it was verified, and how.
ARCHITECTURE.md explains why those choices, what they cost, and the bug classes they exist to prevent.