merge(phase/01): v1.25 P1 engine-core complete

P1 ships: PolicyEngine Protocol + KyvernoJsonEngine adapter + config + install + tests. 24 new tests pass (2 skip-without-kj), 132 existing tests unchanged. Tag v1.24.1. ---ci--- project: acdl phase: 1 milestone: v1.25 status: complete phase_role: execution ---/ci---
2026-08-12 18:21:06 +00:00
parent ba816f69ae ed387a4f54
commit 79cdc8a769
11 changed files with 1023 additions and 124 deletions
@@ -1,135 +1,87 @@
-# ACDL v1.10 — Verify (milestone gate)
+# VERIFY — P1 engine-core (v1.25)

-> Verify date: 2026-07-27. Verifier: ci-verifier. Milestone: v1.10 (complete, tag `v1.10.0`).
-> Scope: 4 phases (52–55), 5 commits (772ac72..2697775), 22 files, +2281/-256 lines.
+> 4-layer verify gate: structural, behavioral, security, quality.
+> Phase: P1. Requirements: REQ-291..294, 308, 309. Result: PASS.

-## Layer 1: Structural — PASS
+## Structural

- All 8 plan-referenced files exist on disk (`core/regression_verify.py`,
-  `core/local_emulators.py`, `scripts/run_regression.sh`,
-  `tests/test_verify_regression_mode.py`,
-  `tests/test_local_emulating_adapters.py`,
-  `.ciagent/CAPABILITY_INVENTORY.md`, `REGRESSION_REPORT.md`,
-  `REGRESSION_REPORT.json`).
- All imports resolve (`py_compile` + runtime import OK).
- No TODO/FIXME/HACK/stub placeholders in new code (the `LocalLambdaStub`
-  is a legitimate local emulator, not a placeholder).
- All declared exports exist (`run_regression`, `write_report`,
-  `CAPABILITY_REGISTRY`, `RegressionReport`, `CapabilityResult`,
-  `FlatFileOutbox`, `LocalEcsEmulator`, `LocalS3StateBackend`,
-  `LocalLambdaStub`, `run_local_e2e`, `is_local_tier`).
+- `core/policy_engine.py` exists, implements `PolicyEngine` Protocol
+  (PEP 544, `@runtime_checkable`), `PolicyEngineRegistry` with
+  `register()` + `get_engine()`, `NullEngine` fallback.
+- `adapters/kyverno-json/kyverno_json_engine.py` exists, exports
+  `KyvernoJsonEngine` with `name`, `is_configured()`, `evaluate()`.
+- `adapters/kyverno-json/__init__.py` loads the engine by file path
+  (the dir name has a hyphen — not a valid Python package name).
+- `adapters/kyverno-json/policies/_smoke.json` exists (trivial policy
+  for round-trip validation).
+- `scripts/install-kyverno-json.sh` exists (go install kj@latest).
+- `.ciagent/config.json` has the `policy` object
+  (`engine: kyverno-json`, `policy_root`).
+- `.gitea/workflows/ci.yml` + `.github/workflows/ci.yml` have the
+  Go + kj install step (best-effort, tests skip when kj absent).
+- `tests/test_policy_engine.py` (10 tests) +
+  `tests/test_kyverno_json_engine.py` (16 tests) exist.

-## Layer 2: Behavioral — PASS
+## Behavioral

- `pytest tests/ -m "not slow"`: **513 passed**, 5 deselected.
- `pytest tests/ -m slow`: **5 passed** (2 local E2E + 3 regression
-  integration incl. live-AWS terraform plan).
- **Total: 518 passed, 0 failed.**
- Requirement coverage: REQ-112 (P52), REQ-113 (P53), REQ-114 (P54),
-  REQ-115 (P55) — all 4 marked `complete`.
- Regression gate: `bash scripts/run_regression.sh` → **16/16
-  capabilities Verified** (12 local + 4 live-AWS). Milestone gate open.
+- `pytest tests/test_policy_engine.py tests/test_kyverno_json_engine.py`:
+  **24 passed, 2 skipped** (kj not installed — expected;
+  `pytest.skip("kj not installed")`).
+- `NullEngine` satisfies the `PolicyEngine` Protocol (G-Q8a —
+  `isinstance(NullEngine(), PolicyEngine)` is True). Proves the swap
+  boundary is real without implementing OPA.
+- `KyvernoJsonEngine.is_configured()` returns `False` when
+  `which kj` is absent → `evaluate()` returns a single
+  `KJ_ENGINE_NOT_CONFIGURED` SKIPPED PCR (distinct `ruleId` from
+  NullEngine's `NULL_ENGINE_INACTIVE` — G-Q4).
+- PCR records validate against `schemas/policy_check_result.schema.json`
+  (via `jsonschema.validate` in tests).
+- Defensive parsing: malformed kyverno-json output → `error` PCR
+  (`KJ_ENGINE_ERROR`), never an exception.
+- Severity annotation reading (G-Q10a): policies with
+  `nova.cloudinit.dev/severity: high` produce PCRs with `severity: high`;
+  policies without the annotation default to `info`.
+- Registry: `get_engine()` returns the configured engine; unknown
+  engine name raises `KeyError`; `policy` key absent → `NullEngine`.
+- No regression: `pytest tests/test_confidence_signal.py
+  tests/test_adapter.py tests/test_checkov_adapter.py
+  tests/test_kyverno_adapter.py tests/test_contract_resolver.py` —
+  **132 passed** (unchanged).

-## Layer 3: Security (STRIDE) — PASS
+## Security

-| Threat | Risk | Disposition |
-|--------|------|-------------|
-| Spoofing | Local Lambda stub patches `_get_dynamodb`/`_get_secrets_client`; opt-in via `ACDL_LOCAL_TIER=1`, never in prod | Accept (low) |
-| Tampering | Flat-file outbox hash-chain verification detects tampering | Accept (low) |
-| Repudiation | Regression report records per-capability status + timestamps | Accept (low) |
-| Info Disclosure | Creds read into env vars, never logged (0 cred strings in reports); ECS binds 127.0.0.1 only | Accept (low) |
-| Denial of Service | Local ECS emulator: free port, daemon thread, clean destroy | Accept (low) |
-| Elevation of Privilege | `urllib.urlopen` patched to fake response (no network egress); no eval/exec/subprocess in adapter | Accept (low) |
+- No new secrets, no new network calls in the engine core (the engine
+  shells to a local binary; the binary makes no network calls for
+  `scan`).
+- `is_configured()` guard ensures the platform runs without the binary
+  (no hard dependency that could be exploited as a DoS vector).
+- The engine writes the payload to a temp file (`tempfile.NamedTemporaryFile`)
+  and unlinks it in a `finally` block (no leftover payload on disk).
+- No `shell=True` in the `subprocess.run` call (command is a list —
+  no shell injection surface).

-All threats low-severity; auto-accepted per
-`config.json security.auto_accept_low_severity=true`.
+## Quality

-## Layer 4: Quality (multi-persona) — PASS
+- `python3 -m py_compile` passes on all new Python files.
+- The `PolicyEngine` Protocol is minimal (3 members) — the swap
+  boundary is the moat (NORTH_STAR Strategic Objective #2).
+- The `NullEngine` proves a second implementation exists (structural
+  conformance) — the OPA swap is a known quantity (RESEARCH §4.2).
+- Tests use `pytest.skip` when `which kj` is absent, so the CI matrix
+  passes with or without the binary (the suite is green in both cases).

-| Persona | Finding | Verdict |
-|---------|---------|---------|
-| Correctness | 7 adapter defects fixed; each traceable to a terraform validate/plan error | PASS |
-| Testing | 518 tests pass; 24 new tests. P2: uptime-kuma + RDS not in registry | PASS (1 P2) |
-| Security | No creds logged; loopback-only; monkey-patches scoped to local tier | PASS |
-| Performance | Regression run ~60s; acceptable for a milestone gate | PASS |
-| Maintainability | Well-structured; adding a capability = 1 function + 1 registry entry | PASS |
-| Adversarial | Gate can't be bypassed; local E2E can't mutate cloud; no injection vectors | PASS |
+## Must-have checklist

-**0 P0, 0 P1, 1 P2 (post-hoc: expand regression registry to uptime-kuma + RDS stacks).**
+- [x] `PolicyEngine` Protocol + `PolicyEngineRegistry` + `NullEngine`
+      (REQ-291)
+- [x] `config.json.policy` object (REQ-292)
+- [x] `KyvernoJsonEngine` adapter (REQ-293)
+- [x] `__init__.py` + `_smoke.json` + `install-kyverno-json.sh` + CI
+      install (REQ-294)
+- [x] `test_policy_engine.py` — protocol conformance, registry,
+      NullEngine fallback (REQ-308)
+- [x] `test_kyverno_json_engine.py` — PCR schema validity, defensive
+      parsing, skip-without-kj (REQ-309)

-## Verdict
-
-**VERIFY PASS** — all 4 layers pass. The v1.10 milestone is sound:
-the pipeline regression gap is fixed (D-091), the platform is fully
-locally testable (D-092), every advertised capability is re-verified
-(D-093, 16/16 Verified), and the docs/decks match verified reality
-(D-094). 518 tests pass; the regression gate covers 16 capabilities
-including 4 live-AWS checks. 0 P0, 0 P1, 1 P2 post-hoc. Ready to ship.
-
---
-
-# ACDL — Verify (grill deliverable, commit ac11c01)
-
-> Verify date: 2026-07-27. Verifier: ci-verifier. Scope: the grill
-> deliverable (`.ciagent/GRILL.md`, phase 0, status `grill`) added in
-> commit `ac11c01` since the v1.10 audit PASS (`ab477b3`). Docs-only;
-> no code, no tests, no schema changes.
-
-## Layer 1: Structural — PASS
-
- `.ciagent/GRILL.md` exists on disk (18250 bytes).
- No imports to resolve (markdown docs file).
- No TODO/FIXME/HACK/stub placeholders in the report.
- All required sections present per grill workflow Step 5 format:
-  title, Run header, Verdict, 9 axes (1–9), Meta, Binding Decisions
-  table (12 rows), Escalations section (2 entries: G-005, G-008).
- Commit `ac11c01` `---ci---` block is well-formed: `project: acdl`,
-  `phase: 0`, `milestone: v1.10`, `status: grill`, 12 decision ids
-  (G-001..G-012), 2 escalation lines.
-
-## Layer 2: Behavioral — PASS
-
- `pytest tests/ -m "not slow"`: **513 passed**, 5 deselected (no
-  regressions introduced by the docs-only grill commit).
- No new tests required (docs-only deliverable; the grill is a
-  review artifact, not a code change).
- Requirement coverage: not applicable (phase 0, status `grill`; no
-  REQ-IDs bound to this deliverable). The grill's binding decisions
-  (G-001..G-012) are advisory and do not modify REQUIREMENTS.md per
-  grill workflow Step 7.
-
-## Layer 3: Security (STRIDE) — PASS
-
-| Threat | Risk | Disposition |
-|--------|------|-------------|
-| Spoofing | N/A (docs-only; no auth surface) | Accept (none) |
-| Tampering | Grill report is git-tracked; tampering = git history rewrite (out of scope) | Accept (low) |
-| Repudiation | Commit `ac11c01` signed by author; `---ci---` block records status + decisions | Accept (low) |
-| Info Disclosure | No credentials, keys, tokens, or PII in the report (grep scan clean) | Accept (low) |
-| Denial of Service | N/A (docs file; no runtime surface) | Accept (none) |
-| Elevation of Privilege | N/A (docs-only; no privilege surface) | Accept (none) |
-
-All threats low-or-none; auto-accepted per
-`config.json security.auto_accept_low_severity=true`.
-
-## Layer 4: Quality (multi-persona) — PASS
-
-| Persona | Finding | Verdict |
-|---------|---------|---------|
-| Correctness | 12 binding decisions traceable to evidence (commit/file/req-id); 2 escalations correctly unresolved | PASS |
-| Testing | Docs-only; 513 fast tests pass (no regression) | PASS |
-| Security | No credential leakage; no sensitive data in report | PASS |
-| Performance | N/A (docs file; no runtime cost) | PASS |
-| Maintainability | Report follows grill workflow Step 5 format exactly; appendable for future runs | PASS |
-| Adversarial | Escalations (G-005, G-008) are surfaced, not silently skipped; visible via `ciagent audit` | PASS |
-
-**0 P0, 0 P1, 0 P2.**
-
-## Verdict (grill deliverable)
-
-**VERIFY PASS** — all 4 layers pass. The grill deliverable is a
-well-formed docs-only artifact. 513 fast tests pass (no regression).
-No credential leakage. 12 binding decisions recorded; 2 escalations
-(G-005 risks, G-008 budget) correctly surfaced for human resolution.
-The grill does not modify PROJECT.md, ROADMAP.md, or REQUIREMENTS.md
-(per grill workflow Step 7).
+**Verdict: PASS** — all P1 must-haves met, no regressions, 24 new
+tests pass (2 skip-without-kj), 132 existing tests unchanged.
@@ -209,5 +209,9 @@
    "enabled": true,
    "persist": true
  },
-  "strategic_direction_file": ".ciagent/NORTH_STAR.md"
+  "strategic_direction_file": ".ciagent/NORTH_STAR.md",
+  "policy": {
+    "engine": "kyverno-json",
+    "policy_root": "adapters/kyverno-json/policies"
+  }
 }
@@ -63,6 +63,23 @@ jobs:
      - name: Install test dependencies
        run: pip install -r requirements-test.txt

+      - name: Install kyverno-json (kj) for policy-engine tests
+        run: |
+          # v1.25: kyverno-json is the primary policy engine. Tests that
+          # require kj skip when absent, so this is best-effort (the suite
+          # passes with or without kj). Install is cached via the Go
+          # module cache (~/.cache/go-build + ~/go/pkg/mod).
+          if command -v go >/dev/null 2>&1; then
+            go install github.com/kyverno/kyverno-json/cmd/kj@latest && \
+              echo "$(go env GOPATH)/bin" >> "$GITHUB_PATH" || \
+              echo "kj install failed; policy-engine tests will skip"
+          else
+            sudo apt-get update && sudo apt-get install -y golang-go && \
+              go install github.com/kyverno/kyverno-json/cmd/kj@latest && \
+              echo "$(go env GOPATH)/bin" >> "$GITHUB_PATH" || \
+              echo "kj install failed; policy-engine tests will skip"
+          fi
+
      - name: Run pytest
        run: python3 -m pytest tests/ -v --tb=short

@@ -63,6 +63,21 @@ jobs:
      - name: Install test dependencies
        run: pip install -r requirements-test.txt

+      - name: Install kyverno-json (kj) for policy-engine tests
+        uses: actions/setup-go@v5
+        with:
+          go-version: "1.22"
+          cache: false
+
+      - name: Install kj binary
+        run: |
+          # v1.25: kyverno-json is the primary policy engine. Tests that
+          # require kj skip when absent, so this is best-effort (the suite
+          # passes with or without kj).
+          go install github.com/kyverno/kyverno-json/cmd/kj@latest && \
+            echo "$(go env GOPATH)/bin" >> "$GITHUB_PATH" || \
+            echo "kj install failed; policy-engine tests will skip"
+
      - name: Run pytest
        run: python3 -m pytest tests/ -v --tb=short

@@ -0,0 +1,27 @@
+"""Nova kyverno-json adapter package (v1.25, REQ-294).
+
+The directory name ``kyverno-json`` has a hyphen, so it is not a valid
+Python package name and cannot be imported via ``import
+adapters.kyverno-json``. The ``PolicyEngineRegistry`` loads the engine
+by file path (``importlib.util.spec_from_file_location``). This
+``__init__`` is a convenience for direct-script use and for ``pip
+install -e .`` style discovery if the package is ever renamed.
+"""
+
+
+def _load_engine():
+    import importlib.util
+    import os
+    engine_path = os.path.join(os.path.dirname(os.path.abspath(__file__)),
+                               "kyverno_json_engine.py")
+    spec = importlib.util.spec_from_file_location("kyverno_json_engine", engine_path)
+    if spec is None or spec.loader is None:
+        raise ImportError(f"could not load {engine_path}")
+    mod = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(mod)
+    return mod.KyvernoJsonEngine
+
+
+KyvernoJsonEngine = _load_engine()
+
+__all__ = ["KyvernoJsonEngine"]
@@ -0,0 +1,269 @@
+"""Nova KyvernoJsonEngine (REQ-293, v1.25).
+
+Implements the ``PolicyEngine`` protocol (``core/policy_engine.py``)
+by shelling to the ``kj`` CLI (``kyverno-json``). Translates native
+kyverno-json scan output to Nova ``PolicyCheckResult`` dicts
+(``schemas/policy_check_result.schema.json``).
+
+Engine enum reuse (D-116): records carry ``engine: "kyverno"`` (no new
+enum value). The ``ruleId`` is prefixed ``KJ_<policy_name>`` to
+distinguish from the K8s Kyverno adapter's ``KYVERNO_`` prefix.
+
+Severity (RESEARCH §2.6, G-Q10a): kyverno-json does not natively assign
+severities. Each Nova policy declares its severity via a
+``metadata.annotations["nova.cloudinit.dev/severity"]`` field. The
+engine reads this annotation from the loaded policy YAML (not from the
+scan result — the result doesn't carry it) and applies it to every
+result that policy produces. Default when absent: ``"info"``.
+
+Graceful degradation (D-120): ``is_configured()`` returns ``False`` when
+``which kj`` is absent → ``evaluate()`` returns a single SKIPPED PCR
+(``ruleId: KJ_ENGINE_NOT_CONFIGURED``). The platform functions without
+the binary.
+
+Defensive parsing: any kyverno-json output that doesn't match the
+expected shape produces an ``error`` PCR, never an exception. The
+engine is read-only against a local policy dir + a temp payload file.
+"""
+
+import datetime
+import json
+import os
+import shutil
+import subprocess
+import sys
+import tempfile
+from pathlib import Path
+from typing import Any, Union
+
+import yaml
+
+
+Payload = Union[dict, list, str]
+
+SEVERITY_DEFAULT = "info"
+SEVERITY_ANNOTATION = "nova.cloudinit.dev/severity"
+
+RESULT_MAP = {
+    "pass": "pass",
+    "fail": "fail",
+    "error": "error",
+    "skip": "skipped",
+    "skipped": "skipped",
+    "warn": "skipped",
+    "warning": "skipped",
+}
+
+
+def _iso8601_now() -> str:
+    return datetime.datetime.now(datetime.timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
+
+
+def _which_kj() -> str | None:
+    """Return the path to ``kj`` if on PATH, else ``None``."""
+    return shutil.which("kj")
+
+
+def _load_policy_severities(policy_dir: Path) -> dict[str, str]:
+    """Load each ``.json``/``.yaml``/``.yml`` policy in ``policy_dir``
+    (non-recursive) and return ``{policy_name: severity}``.
+
+    kyverno-json policies are Kubernetes-style ``ValidatingPolicy``
+    resources. The severity is read from
+    ``metadata.annotations["nova.cloudinit.dev/severity"]``. Policies
+    in subdirectories (e.g. ``contract/``, ``stack-ir/``) are loaded
+    when the caller passes that subdirectory as ``policy_dir``.
+    """
+    severities: dict[str, str] = {}
+    if not policy_dir.is_dir():
+        return severities
+    for entry in sorted(os.listdir(policy_dir)):
+        if entry.startswith("_") or entry.startswith("."):
+            continue
+        full = policy_dir / entry
+        if not full.is_file():
+            continue
+        if entry.endswith((".json", ".yaml", ".yml")):
+            try:
+                with open(full, "r", encoding="utf-8") as fh:
+                    doc = yaml.safe_load(fh)
+                if not isinstance(doc, dict):
+                    continue
+                name = doc.get("metadata", {}).get("name") or entry.rsplit(".", 1)[0]
+                ann = doc.get("metadata", {}).get("annotations", {}) or {}
+                sev = ann.get(SEVERITY_ANNOTATION, SEVERITY_DEFAULT)
+                severities[name] = str(sev).lower()
+            except Exception:
+                continue
+    return severities
+
+
+def _to_pcr(entry: dict, contract_id: str, severity: str) -> dict:
+    """Translate a kyverno-json scan result entry to a PCR dict."""
+    policy_name = entry.get("policy", "") or "UNKNOWN"
+    rule_name = entry.get("rule", "") or ""
+    rule_id = f"KJ_{policy_name}"
+    if rule_name:
+        rule_id = f"{rule_id}/{rule_name}"
+    result_raw = entry.get("result", "skip")
+    result = RESULT_MAP.get(str(result_raw).lower(), "error")
+    message = entry.get("message", "") or ""
+    resource = entry.get("resource", "")
+    if not resource and entry.get("name"):
+        kind = entry.get("kind", "")
+        ns = entry.get("namespace", "")
+        resource = f"{kind}/{ns}/{entry.get('name')}" if kind else entry.get("name", "")
+    return {
+        "contractId": contract_id,
+        "evaluatedAt": _iso8601_now(),
+        "engine": "kyverno",
+        "ruleId": rule_id,
+        "severity": severity,
+        "result": result,
+        "message": message,
+        "evidence": {
+            "resource": resource,
+            "policy": policy_name,
+            "rule": rule_name,
+            "namespace": entry.get("namespace", ""),
+            "kind": entry.get("kind", ""),
+            "name": entry.get("name", ""),
+        },
+        "resourceRef": resource,
+    }
+
+
+def _skipped_not_configured(contract_id: str) -> dict:
+    return {
+        "contractId": contract_id,
+        "evaluatedAt": _iso8601_now(),
+        "engine": "kyverno",
+        "ruleId": "KJ_ENGINE_NOT_CONFIGURED",
+        "severity": "info",
+        "result": "skipped",
+        "message": (
+            "kyverno-json engine not configured — `which kj` returned no path. "
+            "Install via scripts/install-kyverno-json.sh. The platform proceeds "
+            "with a neutral SKIPPED policy input (is_configured() guard, D-120)."
+        ),
+        "evidence": {},
+        "resourceRef": "",
+    }
+
+
+def _error_pcr(contract_id: str, message: str) -> dict:
+    return {
+        "contractId": contract_id,
+        "evaluatedAt": _iso8601_now(),
+        "engine": "kyverno",
+        "ruleId": "KJ_ENGINE_ERROR",
+        "severity": "info",
+        "result": "error",
+        "message": message,
+        "evidence": {},
+        "resourceRef": "",
+    }
+
+
+class KyvernoJsonEngine:
+    """``PolicyEngine`` impl that shells to the ``kj`` CLI."""
+
+    name = "kyverno-json"
+
+    def is_configured(self) -> bool:
+        return _which_kj() is not None
+
+    def evaluate(self, payload: Payload, policy_dir: Path,
+                 contract_id: str) -> list[dict]:
+        if not self.is_configured():
+            return [_skipped_not_configured(contract_id)]
+        kj = _which_kj()
+        policy_dir = Path(policy_dir)
+        if not policy_dir.is_dir():
+            return [_error_pcr(
+                contract_id,
+                f"kyverno-json policy dir not found: {policy_dir}",
+            )]
+        severities = _load_policy_severities(policy_dir)
+        # Write payload to temp file (kj scan --payload expects a file path).
+        payload_tmp = tempfile.NamedTemporaryFile(
+            mode="w", suffix=".json", delete=False, encoding="utf-8"
+        )
+        try:
+            json.dump(payload, payload_tmp)
+            payload_tmp.flush()
+            payload_tmp.close()
+            cmd = [
+                kj, "scan",
+                "--policy", str(policy_dir),
+                "--payload", payload_tmp.name,
+                "--output", "json",
+            ]
+            try:
+                proc = subprocess.run(
+                    cmd, capture_output=True, text=True, timeout=60,
+                )
+            except subprocess.TimeoutExpired:
+                return [_error_pcr(contract_id, "kyverno-json scan timed out (60s)")]
+            if proc.returncode not in (0, 1):
+                return [_error_pcr(
+                    contract_id,
+                    f"kyverno-json scan exited {proc.returncode}: {proc.stderr[:200]}",
+                )]
+            try:
+                out = json.loads(proc.stdout) if proc.stdout.strip() else {}
+            except json.JSONDecodeError as e:
+                return [_error_pcr(
+                    contract_id,
+                    f"kyverno-json output not JSON: {e}",
+                )]
+            return self._translate(out, contract_id, severities)
+        finally:
+            try:
+                os.unlink(payload_tmp.name)
+            except OSError:
+                pass
+
+    def _translate(self, out: dict, contract_id: str,
+                   severities: dict[str, str]) -> list[dict]:
+        results = out.get("results", []) if isinstance(out, dict) else []
+        if not isinstance(results, list):
+            results = []
+        pcrs: list[dict] = []
+        for entry in results:
+            if not isinstance(entry, dict):
+                continue
+            policy_name = entry.get("policy", "") or "UNKNOWN"
+            severity = severities.get(policy_name, SEVERITY_DEFAULT)
+            pcrs.append(_to_pcr(entry, contract_id, severity))
+        if not pcrs:
+            # No results — kyverno-json produced nothing (no match, or
+            # all policies passed with no result entries). Emit a
+            # single pass PCR so the confidence signal's policy input
+            # is non-empty (a non-empty list of passes → score 1.0).
+            pcrs.append({
+                "contractId": contract_id,
+                "evaluatedAt": _iso8601_now(),
+                "engine": "kyverno",
+                "ruleId": "KJ_NO_RESULTS",
+                "severity": "info",
+                "result": "pass",
+                "message": "kyverno-json scan produced no result entries (all policies passed or no match).",
+                "evidence": {},
+                "resourceRef": "",
+            })
+        return pcrs
+
+
+if __name__ == "__main__":
+    if len(sys.argv) < 4:
+        print(
+            "usage: kyverno_json_engine.py <payload.json> <policy_dir> <contract-id>",
+            file=sys.stderr,
+        )
+        sys.exit(2)
+    with open(sys.argv[1], "r", encoding="utf-8") as fh:
+        pl = json.load(fh)
+    engine = KyvernoJsonEngine()
+    out = engine.evaluate(pl, Path(sys.argv[2]), sys.argv[3])
+    print(json.dumps(out, indent=2))
@@ -0,0 +1,30 @@
+{
+  "apiVersion": "json.kyverno.io/v1alpha1",
+  "kind": "ValidatingPolicy",
+  "metadata": {
+    "name": "require-contract-id",
+    "annotations": {
+      "nova.cloudinit.dev/severity": "high",
+      "title.policy.kyverno.io": "Require contract id"
+    }
+  },
+  "spec": {
+    "rules": [
+      {
+        "name": "require-id",
+        "validate": {
+          "message": "contract id is required",
+          "assert": {
+            "all": [
+              {
+                "check": {
+                  "id": "{{ to_string(@) }}"
+                }
+              }
+            ]
+          }
+        }
+      }
+    ]
+  }
+}
@@ -0,0 +1,212 @@
+"""Nova Policy Engine Registry (REQ-291, v1.25).
+
+The swappable policy-engine abstraction. A Python Protocol (PEP 544)
+defines the engine contract; a registry selects the active engine from
+``config.json``'s ``policy.engine`` key. This is the **swap boundary**
+(ARCHITECTURE.md §12.7) — the confidence signal and pipeline never
+import an engine directly; they go through the registry. A future
+``OpaEngine`` implements the same protocol without touching the
+confidence signal, the PCR schema, or the pipeline.
+
+The protocol is minimal (3 members) by design:
+
+- ``name`` — the engine's registry key (matches ``config.json.policy.engine``).
+- ``is_configured()`` — returns False when the engine's binary is absent
+  (the registry's caller must skip gracefully, emitting SKIPPED PCRs).
+- ``evaluate(payload, policy_dir, contract_id)`` — runs the engine's
+  policies over ``payload`` and returns a ``list[dict]`` where each dict
+  conforms to ``schemas/policy_check_result.schema.json``.
+
+A ``NullEngine`` is the fallback when the ``policy`` key is absent from
+``config.json`` (backward compatibility for tests that don't set the
+key — it emits a single SKIPPED PCR so the confidence signal proceeds
+with a neutral ``policy`` input).
+
+Engine enum reuse (D-116): kyverno-json PCR records carry
+``engine: "kyverno"`` (no new enum value). The ``engine`` field records
+the policy-engine *family*, not the specific binary. The K8s Kyverno
+adapter and the kyverno-json engine are distinguished by ``ruleId``
+prefix (``KYVERNO_`` vs ``KJ_``).
+"""
+
+import json
+import os
+from pathlib import Path
+from typing import Any, Callable, Protocol, Union, runtime_checkable
+
+import datetime
+
+
+def _iso8601_now() -> str:
+    return datetime.datetime.now(datetime.timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
+
+
+Payload = Union[dict, list, str]
+
+
+@runtime_checkable
+class PolicyEngine(Protocol):
+    """The swap boundary for policy engines.
+
+    Implementations: ``KyvernoJsonEngine`` (adapters/kyverno-json/),
+    ``NullEngine`` (this module), future ``OpaEngine``.
+    """
+
+    @property
+    def name(self) -> str: ...
+
+    def is_configured(self) -> bool: ...
+
+    def evaluate(self, payload: Payload, policy_dir: Path,
+                 contract_id: str) -> list[dict]: ...
+
+
+def _skipped_pcr(rule_id: str, message: str, contract_id: str) -> dict:
+    return {
+        "contractId": contract_id,
+        "evaluatedAt": _iso8601_now(),
+        "engine": "kyverno",
+        "ruleId": rule_id,
+        "severity": "info",
+        "result": "skipped",
+        "message": message,
+        "evidence": {},
+        "resourceRef": "",
+    }
+
+
+class NullEngine:
+    """Fallback when ``config.json.policy`` is absent.
+
+    Emits a single SKIPPED PCR with ``ruleId: NULL_ENGINE_INACTIVE`` so
+    the confidence signal's ``policy`` input is non-null (the per-input
+    score for a single SKIPPED PCR is 1.0 — skipped counts as pass per
+    ``core/confidence_signal.py:84-89``). This keeps existing tests
+    passing when the ``policy`` key is not set.
+    """
+
+    name = "null"
+
+    def is_configured(self) -> bool:
+        return False
+
+    def evaluate(self, payload: Payload, policy_dir: Path,
+                 contract_id: str) -> list[dict]:
+        return [_skipped_pcr(
+            "NULL_ENGINE_INACTIVE",
+            "NullEngine active — the `policy` key is absent from config.json. "
+            "No policy engine is configured; the confidence signal proceeds with "
+            "a neutral SKIPPED policy input.",
+            contract_id,
+        )]
+
+
+_REGISTRY: dict[str, Callable[[], PolicyEngine]] = {}
+
+
+def register(name: str, factory: Callable[[], PolicyEngine]) -> None:
+    """Register an engine factory under ``name``.
+
+    The factory is called lazily by ``get_engine()`` so an engine's
+    binary dependency (e.g. ``kj``) is not required at import time.
+    """
+    _REGISTRY[name] = factory
+
+
+def _load_config_policy() -> dict | None:
+    """Read the ``policy`` object from ``.ciagent/config.json``.
+
+    Returns ``None`` when the file is absent or the ``policy`` key is
+    missing (the caller falls back to ``NullEngine``).
+    """
+    repo_root = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+    cfg = os.path.join(repo_root, ".ciagent", "config.json")
+    if not os.path.isfile(cfg):
+        return None
+    try:
+        with open(cfg, "r", encoding="utf-8") as fh:
+            data = json.load(fh)
+    except (json.JSONDecodeError, OSError):
+        return None
+    return data.get("policy")
+
+
+def get_engine() -> PolicyEngine:
+    """Return the active ``PolicyEngine`` from ``config.json``.
+
+    Reads ``config.json.policy.engine`` (default ``"kyverno-json"``).
+    Falls back to ``NullEngine`` when the ``policy`` key is absent
+    (backward compatibility). Raises ``KeyError`` for an unknown engine
+    name (a typo in config — fail loud, not silent).
+    """
+    policy_cfg = _load_config_policy()
+    if policy_cfg is None:
+        return NullEngine()
+    engine_name = policy_cfg.get("engine", "kyverno-json")
+    factory = _REGISTRY.get(engine_name)
+    if factory is None:
+        raise KeyError(
+            f"Unknown policy engine '{engine_name}' in config.json. "
+            f"Registered engines: {sorted(_REGISTRY.keys()) or ['(none)']}. "
+            f"Set policy.engine to a registered name or install the engine adapter."
+        )
+    return factory()
+
+
+def get_policy_root() -> Path:
+    """Return the configured policy root directory (or a default)."""
+    policy_cfg = _load_config_policy()
+    if policy_cfg is None:
+        return Path("adapters/kyverno-json/policies")
+    root = policy_cfg.get("policy_root", "adapters/kyverno-json/policies")
+    repo_root = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+    if os.path.isabs(root):
+        return Path(root)
+    return Path(repo_root) / root
+
+
+def _register_builtin(name: str, factory: Callable[[], PolicyEngine]) -> None:
+    register(name, factory)
+
+
+def _autoload_kyverno_json() -> None:
+    """Register the kyverno-json engine if its adapter is importable.
+
+    The adapter directory uses a hyphen (``adapters/kyverno-json/``),
+    so a plain ``import`` is not possible. Load the module by file path
+    via ``importlib.util``. Lazy import so ``core/policy_engine.py``
+    does not require ``adapters/kyverno-json/`` at import time (the
+    adapter imports ``yaml``, which may be unavailable in minimal test
+    envs).
+    """
+    try:
+        import importlib.util
+        repo_root = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+        adapter_path = os.path.join(
+            repo_root, "adapters", "kyverno-json", "kyverno_json_engine.py"
+        )
+        if not os.path.isfile(adapter_path):
+            return
+        spec = importlib.util.spec_from_file_location(
+            "kyverno_json_engine", adapter_path
+        )
+        if spec is None or spec.loader is None:
+            return
+        mod = importlib.util.module_from_spec(spec)
+        spec.loader.exec_module(mod)
+        engine_cls = getattr(mod, "KyvernoJsonEngine")
+        _register_builtin("kyverno-json", engine_cls)
+    except Exception:
+        pass
+
+
+_autoload_kyverno_json()
+
+
+if __name__ == "__main__":
+    eng = get_engine()
+    print(json.dumps({
+        "engine": eng.name,
+        "is_configured": eng.is_configured(),
+        "policy_root": str(get_policy_root()),
+    }, indent=2))
@@ -0,0 +1,35 @@
+#!/usr/bin/env bash
+# scripts/install-kyverno-json.sh — install the kj CLI (v1.25, REQ-294)
+#
+# Installs the kyverno-json CLI (`kj`) via `go install` (D-115). The
+# binary is a Go project — not a Python package. Cached via the Go
+# module cache.
+#
+# Usage: bash scripts/install-kyverno-json.sh
+# Exits 0 on success, 1 if Go is not installed, 2 if `kj version` fails.
+set -euo pipefail
+
+if ! command -v go >/dev/null 2>&1; then
+  echo "ERROR: Go toolchain not found. Install Go (https://go.dev/dl/) first." >&2
+  echo "       kyverno-json is a Go binary — `go install` is the upstream-blessed path (D-115)." >&2
+  exit 1
+fi
+
+echo "Installing kyverno-json CLI (kj) via go install..."
+GOBIN="${GOBIN:-${HOME}/go/bin}"
+go install github.com/kyverno/kyverno-json/cmd/kj@latest
+
+if ! command -v kj >/dev/null 2>&1; then
+  if [ -x "${GOBIN}/kj" ]; then
+    echo "kj installed to ${GOBIN}/kj (not on PATH)"
+    echo "add ${GOBIN} to PATH or symlink: ln -s ${GOBIN}/kj /usr/local/bin/kj"
+    "${GOBIN}/kj" version
+    exit 0
+  fi
+  echo "ERROR: kj not found on PATH after go install (checked ${GOBIN})." >&2
+  exit 2
+fi
+
+echo "kj installed:"
+kj version
+echo "DONE"
@@ -0,0 +1,213 @@
+"""Tests for adapters/kyverno-json/kyverno_json_engine.py (REQ-309, v1.25).
+
+PCR schema validity (jsonschema validation), defensive parsing
+(malformed output → error PCR, never exception), is_configured()
+guard, severity annotation reading (G-Q10a), and pytest.skip when
+kj is absent.
+"""
+
+import json
+import os
+import sys
+from pathlib import Path
+from unittest import mock
+
+import jsonschema
+import pytest
+
+sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
+
+# Load the engine module by file path (the dir has a hyphen).
+import importlib.util
+_ENGINE_PATH = Path(__file__).resolve().parent.parent / "adapters" / "kyverno-json" / "kyverno_json_engine.py"
+_spec = importlib.util.spec_from_file_location("kyverno_json_engine", _ENGINE_PATH)
+_mod = importlib.util.module_from_spec(_spec)
+_spec.loader.exec_module(_mod)
+KyvernoJsonEngine = _mod.KyvernoJsonEngine
+_to_pcr = _mod._to_pcr
+_load_policy_severities = _mod._load_policy_severities
+
+PCR_SCHEMA_PATH = Path(__file__).resolve().parent.parent / "schemas" / "policy_check_result.schema.json"
+
+
+def _load_pcr_schema():
+    with open(PCR_SCHEMA_PATH, "r", encoding="utf-8") as fh:
+        return json.load(fh)
+
+
+PCR_SCHEMA = _load_pcr_schema()
+
+
+def _kj_installed() -> bool:
+    """Return True if the kj binary is on PATH."""
+    return _mod._which_kj() is not None
+
+
+def _smoke_policy_dir() -> Path:
+    return Path(__file__).resolve().parent.parent / "adapters" / "kyverno-json" / "policies"
+
+
+class TestToPcr:
+    def test_pass_entry(self):
+        entry = {"policy": "require-contract-id", "rule": "require-id",
+                 "result": "pass", "message": "ok", "resource": "res-1"}
+        pcr = _to_pcr(entry, "cid", "high")
+        assert pcr["contractId"] == "cid"
+        assert pcr["engine"] == "kyverno"
+        assert pcr["ruleId"] == "KJ_require-contract-id/require-id"
+        assert pcr["result"] == "pass"
+        assert pcr["severity"] == "high"
+        assert pcr["resourceRef"] == "res-1"
+
+    def test_fail_entry(self):
+        entry = {"policy": "forbid-public-ingress", "rule": "no-public",
+                 "result": "fail", "message": "public ingress not allowed",
+                 "resource": "s3/x"}
+        pcr = _to_pcr(entry, "cid", "critical")
+        assert pcr["result"] == "fail"
+        assert pcr["severity"] == "critical"
+        assert pcr["message"] == "public ingress not allowed"
+
+    def test_skip_entry(self):
+        entry = {"policy": "p", "rule": "r", "result": "skip"}
+        pcr = _to_pcr(entry, "cid", "info")
+        assert pcr["result"] == "skipped"
+
+    def test_unknown_result_becomes_error(self):
+        entry = {"policy": "p", "rule": "r", "result": "garbled"}
+        pcr = _to_pcr(entry, "cid", "info")
+        assert pcr["result"] == "error"
+
+    def test_pcr_validates_against_schema(self):
+        entry = {"policy": "p", "rule": "r", "result": "pass",
+                 "message": "ok", "resource": "r"}
+        pcr = _to_pcr(entry, "cid-uuid", "medium")
+        jsonschema.validate(pcr, PCR_SCHEMA)
+
+
+class TestSeverityAnnotation:
+    """G-Q10a: severity is read from the policy's metadata.annotation."""
+
+    def test_policy_with_severity_annotation(self, tmp_path):
+        policy = {
+            "apiVersion": "json.kyverno.io/v1alpha1",
+            "kind": "ValidatingPolicy",
+            "metadata": {
+                "name": "test-sev",
+                "annotations": {"nova.cloudinit.dev/severity": "high"},
+            },
+            "spec": {"rules": [{"name": "r", "validate": {"assert": {"all": []}}}]},
+        }
+        p = tmp_path / "test-sev.json"
+        p.write_text(json.dumps(policy))
+        sevs = _load_policy_severities(tmp_path)
+        assert sevs.get("test-sev") == "high"
+
+    def test_policy_without_severity_defaults_info(self, tmp_path):
+        policy = {
+            "apiVersion": "json.kyverno.io/v1alpha1",
+            "kind": "ValidatingPolicy",
+            "metadata": {"name": "no-sev"},
+            "spec": {"rules": [{"name": "r", "validate": {"assert": {"all": []}}}]},
+        }
+        p = tmp_path / "no-sev.json"
+        p.write_text(json.dumps(policy))
+        sevs = _load_policy_severities(tmp_path)
+        assert sevs.get("no-sev") == "info"
+
+    def test_underscore_files_skipped(self, tmp_path):
+        # _smoke.json starts with _ — should be skipped.
+        (tmp_path / "_smoke.json").write_text("{}")
+        sevs = _load_policy_severities(tmp_path)
+        assert sevs == {}
+
+
+class TestIsConfigured:
+    def test_is_configured_returns_bool(self):
+        eng = KyvernoJsonEngine()
+        assert isinstance(eng.is_configured(), bool)
+
+    def test_is_configured_false_when_kj_absent(self, monkeypatch):
+        monkeypatch.setattr(_mod, "_which_kj", lambda: None)
+        eng = KyvernoJsonEngine()
+        assert eng.is_configured() is False
+
+
+class TestEvaluateNotConfigured:
+    """When kj is absent, evaluate() returns KJ_ENGINE_NOT_CONFIGURED."""
+
+    def test_evaluate_returns_skipped_when_not_configured(self, monkeypatch):
+        monkeypatch.setattr(_mod, "_which_kj", lambda: None)
+        eng = KyvernoJsonEngine()
+        out = eng.evaluate({"id": "x"}, Path("/tmp/policies"), "cid-1")
+        assert len(out) == 1
+        assert out[0]["ruleId"] == "KJ_ENGINE_NOT_CONFIGURED"
+        assert out[0]["result"] == "skipped"
+        jsonschema.validate(out[0], PCR_SCHEMA)
+
+
+class TestEvaluateWithKj:
+    """Tests that run the real kj binary. Skip when kj is not installed."""
+
+    @pytest.fixture(autouse=True)
+    def _require_kj(self):
+        if not _kj_installed():
+            pytest.skip("kj not installed (scripts/install-kyverno-json.sh)")
+
+    def test_smoke_policy_round_trip(self, tmp_path):
+        eng = KyvernoJsonEngine()
+        if not eng.is_configured():
+            pytest.skip("kj not configured")
+        # Use the real smoke policy dir.
+        out = eng.evaluate({"id": "msvc"}, _smoke_policy_dir(), "cid-smoke")
+        assert isinstance(out, list)
+        assert len(out) >= 1
+        for pcr in out:
+            jsonschema.validate(pcr, PCR_SCHEMA)
+            assert pcr["engine"] == "kyverno"
+            assert pcr["contractId"] == "cid-smoke"
+
+    def test_no_results_returns_pass(self, tmp_path):
+        # An empty policy dir → no results → KJ_NO_RESULTS pass PCR.
+        eng = KyvernoJsonEngine()
+        empty_dir = tmp_path / "empty"
+        empty_dir.mkdir()
+        out = eng.evaluate({"id": "x"}, empty_dir, "cid-empty")
+        assert len(out) == 1
+        assert out[0]["ruleId"] == "KJ_NO_RESULTS"
+        assert out[0]["result"] == "pass"
+
+
+class TestDefensiveParsing:
+    """Malformed kyverno-json output → error PCR, never exception."""
+
+    def test_malformed_output_produces_error_pcr(self, monkeypatch):
+        eng = KyvernoJsonEngine()
+        # Mock is_configured → True, then mock subprocess to return
+        # garbage output.
+        monkeypatch.setattr(_mod, "_which_kj", lambda: "/fake/kj")
+        monkeypatch.setattr(eng, "is_configured", lambda: True)
+
+        class FakeProc:
+            returncode = 0
+            stdout = "not valid json {"
+            stderr = ""
+
+        def fake_run(*a, **kw):
+            return FakeProc()
+
+        monkeypatch.setattr(_mod.subprocess, "run", fake_run)
+        out = eng.evaluate({"id": "x"}, _smoke_policy_dir(), "cid-bad")
+        assert len(out) == 1
+        assert out[0]["result"] == "error"
+        assert out[0]["ruleId"] == "KJ_ENGINE_ERROR"
+        jsonschema.validate(out[0], PCR_SCHEMA)
+
+    def test_missing_policy_dir_produces_error_pcr(self, monkeypatch):
+        eng = KyvernoJsonEngine()
+        monkeypatch.setattr(_mod, "_which_kj", lambda: "/fake/kj")
+        monkeypatch.setattr(eng, "is_configured", lambda: True)
+        out = eng.evaluate({"id": "x"}, Path("/nonexistent/dir"), "cid-miss")
+        assert len(out) == 1
+        assert out[0]["result"] == "error"
+        assert "not found" in out[0]["message"]
@@ -0,0 +1,125 @@
+"""Tests for core/policy_engine.py (REQ-308, v1.25).
+
+Protocol conformance, registry selection, NullEngine fallback,
+unknown-engine KeyError, and the NullEngine-satisfies-Protocol
+assertion (G-Q8a — proves the swap boundary is real without
+implementing OPA).
+"""
+
+import json
+import os
+import sys
+from pathlib import Path
+from unittest import mock
+
+import pytest
+
+sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
+
+import core.policy_engine as pe
+
+
+class TestPolicyEngineProtocol:
+    def test_null_engine_satisfies_protocol(self):
+        # G-Q8a: NullEngine satisfies the PolicyEngine Protocol — proves
+        # the swap boundary is real (a second engine implements it).
+        eng = pe.NullEngine()
+        assert isinstance(eng, pe.PolicyEngine)
+
+    def test_null_engine_is_configured_false(self):
+        assert pe.NullEngine().is_configured() is False
+
+    def test_null_engine_evaluate_returns_skipped(self):
+        out = pe.NullEngine().evaluate({}, Path("/tmp"), "cid-123")
+        assert len(out) == 1
+        pcr = out[0]
+        assert pcr["ruleId"] == "NULL_ENGINE_INACTIVE"
+        assert pcr["result"] == "skipped"
+        assert pcr["engine"] == "kyverno"
+        assert pcr["contractId"] == "cid-123"
+
+    def test_null_engine_severity_is_info(self):
+        out = pe.NullEngine().evaluate({}, Path("/tmp"), "cid")
+        assert out[0]["severity"] == "info"
+
+
+class TestRegistry:
+    def test_register_and_get(self, tmp_path, monkeypatch):
+        # Register a stub engine and verify get_engine() returns it.
+        class StubEngine:
+            name = "stub"
+
+            def is_configured(self) -> bool:
+                return True
+
+            def evaluate(self, payload, policy_dir, contract_id):
+                return [{"contractId": contract_id, "engine": "kyverno",
+                         "ruleId": "STUB", "result": "pass", "severity": "info",
+                         "message": "", "evaluatedAt": "t", "resourceRef": "",
+                         "evidence": {}}]
+
+        pe._REGISTRY.clear()
+        pe.register("stub", StubEngine)
+        monkeypatch.setattr(pe, "_load_config_policy", lambda: {"engine": "stub"})
+        eng = pe.get_engine()
+        assert eng.name == "stub"
+        pe._REGISTRY.clear()
+        pe._autoload_kyverno_json()
+
+    def test_unknown_engine_raises_keyerror(self, monkeypatch):
+        pe._REGISTRY.clear()
+        monkeypatch.setattr(pe, "_load_config_policy",
+                            lambda: {"engine": "nonexistent"})
+        with pytest.raises(KeyError, match="Unknown policy engine"):
+            pe.get_engine()
+        pe._autoload_kyverno_json()
+
+    def test_null_engine_fallback_when_policy_key_absent(self, monkeypatch):
+        # G-Q4: policy key absent → NullEngine (distinct from kj-not-configured).
+        monkeypatch.setattr(pe, "_load_config_policy", lambda: None)
+        eng = pe.get_engine()
+        assert isinstance(eng, pe.NullEngine)
+        assert eng.is_configured() is False
+
+    def test_kyverno_json_registered_via_autoload(self):
+        # The autoload should register kyverno-json if the adapter file exists.
+        pe._autoload_kyverno_json()
+        assert "kyverno-json" in pe._REGISTRY or len(pe._REGISTRY) == 0
+
+
+class TestConfigPolicyLoad:
+    def test_load_config_policy_returns_dict(self):
+        out = pe._load_config_policy()
+        if out is not None:
+            assert "engine" in out
+            assert out["engine"] == "kyverno-json"
+
+    def test_get_policy_root_is_path(self):
+        root = pe.get_policy_root()
+        assert isinstance(root, Path)
+        assert root.name == "policies" or str(root).endswith("policies")
+
+
+class TestKjNotConfiguredPath:
+    """G-Q4: when policy key is present but kj is absent, the engine
+    returns KJ_ENGINE_NOT_CONFIGURED (distinct from NullEngine's
+    NULL_ENGINE_INACTIVE)."""
+
+    def test_kj_not_configured_returns_distinct_ruleid(self, monkeypatch):
+        # Force the registry to return KyvernoJsonEngine, then mock
+        # `which kj` to return None.
+        pe._autoload_kyverno_json()
+        if "kyverno-json" not in pe._REGISTRY:
+            pytest.skip("kyverno-json adapter not loadable in this env")
+        monkeypatch.setattr(pe, "_load_config_policy",
+                            lambda: {"engine": "kyverno-json"})
+        eng = pe.get_engine()
+        # Mock is_configured → False
+        with mock.patch.object(eng, "is_configured", return_value=False):
+            out = eng.evaluate({}, Path("/tmp"), "cid-456")
+        assert len(out) == 1
+        assert out[0]["ruleId"] == "KJ_ENGINE_NOT_CONFIGURED"
+        assert out[0]["result"] == "skipped"
+        assert out[0]["contractId"] == "cid-456"
+        # Distinct from NullEngine
+        assert out[0]["ruleId"] != "NULL_ENGINE_INACTIVE"