stabilize tests

src/Cryptography/AGENTS.md

@@ -0,0 +1,24 @@
+# AGENTS - Cryptography Module
+
+## Working Directory
+- `src/Cryptography/**` (crypto core, plugins, profiles, tests).
+
+## Required Reading
+- `docs/README.md`
+- `docs/07_HIGH_LEVEL_ARCHITECTURE.md`
+- `docs/modules/platform/architecture-overview.md`
+- `docs/modules/cryptography/architecture.md`
+- `docs/modules/cryptography/README.md`
+- `docs/modules/cryptography/multi-profile-signing-specification.md`
+
+## Engineering Rules
+- Deterministic serialization and signing; no nondeterministic inputs.
+- Respect offline posture; no network calls in crypto paths.
+- Validate inputs and fail closed on verification errors.
+
+## Testing & Verification
+- Tests live in `src/Cryptography/__Tests/**`.
+- Add vectors for signing/verification, negative cases, and determinism.
+
+## Sprint Discipline
+- Log cryptography decisions in sprint Decisions & Risks with doc links.