diff --git a/test/helpers/carve-guard-checks.ts b/test/helpers/carve-guard-checks.ts
new file mode 100644
index 000000000..829cd8d92
--- /dev/null
+++ b/test/helpers/carve-guard-checks.ts
@@ -0,0 +1,162 @@
+/**
+ * Pure carve-guard check functions, with an injectable `root` (codex
+ * outside-voice #5, refined-plan pass) so the negative tests (T5) can point the
+ * REAL guards at a broken fixture dir instead of testing a wrapper.
+ *
+ * Used by:
+ *   - test/carve-section-ordering.test.ts    (E2)  → checkOrdering
+ *   - test/carve-guard-completeness.test.ts  (E1)  → discoverCarvedSkills + checkCompleteness
+ *   - test/carve-guards-negative.test.ts     (T5)  → both, against a fixture root
+ *
+ * Imports only the leaf data module (carve-guards.ts) + node stdlib — no cycle.
+ */
+
+import * as fs from 'fs';
+import * as path from 'path';
+import { CARVE_GUARDS, type CarveGuard } from './carve-guards';
+
+/** Every dir under `root` that owns a sections/manifest.json. Injectable for tests. */
+export function discoverCarvedSkills(root: string): string[] {
+  return fs
+    .readdirSync(root, { withFileTypes: true })
+    .filter((d) => d.isDirectory())
+    .map((d) => d.name)
+    .filter((name) => fs.existsSync(path.join(root, name, 'sections', 'manifest.json')))
+    .sort();
+}
+
+function readSkeleton(root: string, skill: string): string {
+  return fs.readFileSync(path.join(root, skill, 'SKILL.md'), 'utf-8');
+}
+
+/** Skeleton + every sections/*.md unioned (relocated content still counts). */
+function readUnion(root: string, skill: string): string {
+  let text = readSkeleton(root, skill);
+  const dir = path.join(root, skill, 'sections');
+  if (fs.existsSync(dir)) {
+    for (const f of fs.readdirSync(dir).sort()) {
+      if (f.endsWith('.md') && !f.endsWith('.md.tmpl')) {
+        text += '\n' + fs.readFileSync(path.join(dir, f), 'utf-8');
+      }
+    }
+  }
+  return text;
+}
+
+const STOP = '> **STOP.**';
+
+/**
+ * Static ordering invariants for one carved skill. Returns a list of failure
+ * strings (empty = pass). Pure: takes `root` so it runs against the real repo or
+ * a fixture identically.
+ */
+export function checkOrdering(root: string, guard: CarveGuard): string[] {
+  const failures: string[] = [];
+  let skeleton: string;
+  try {
+    skeleton = readSkeleton(root, guard.skill);
+  } catch (err) {
+    return [`cannot read ${guard.skill}/SKILL.md: ${(err as Error).message}`];
+  }
+  const union = readUnion(root, guard.skill);
+
+  // 1. The skeleton routes to sections via a Section index + STOP-Read directives.
+  if (!skeleton.includes('## Section index')) {
+    failures.push('skeleton is missing the "## Section index" table');
+  }
+  if (!skeleton.includes(STOP)) {
+    failures.push('skeleton has no STOP-Read directive');
+  }
+
+  // 2. Every expected section is referenced by path AND generated (AUTO-GENERATED).
+  for (const file of guard.expectedSections) {
+    if (!skeleton.includes(`sections/${file}`)) {
+      failures.push(`skeleton does not reference sections/${file}`);
+    }
+    const secPath = path.join(root, guard.skill, 'sections', file);
+    if (!fs.existsSync(secPath)) {
+      failures.push(`section file missing: sections/${file}`);
+    } else if (!fs.readFileSync(secPath, 'utf-8').slice(0, 200).includes('AUTO-GENERATED')) {
+      failures.push(`sections/${file} is hand-edited (no AUTO-GENERATED header)`);
+    }
+  }
+
+  // 3. Pre-STOP anchors stay in the skeleton.
+  for (const anchor of guard.staticInvariants.mustStayInSkeleton) {
+    if (!skeleton.includes(anchor)) {
+      failures.push(`mustStayInSkeleton anchor missing from skeleton: "${anchor}"`);
+    }
+  }
+
+  // 4. Heavy body moved out of the skeleton but is preserved in the union.
+  for (const moved of guard.staticInvariants.mustMoveToSection) {
+    if (skeleton.includes(moved)) {
+      failures.push(`mustMoveToSection marker is still in the skeleton: "${moved}"`);
+    }
+    if (!union.includes(moved)) {
+      failures.push(`mustMoveToSection marker absent from the union (lost): "${moved}"`);
+    }
+  }
+
+  // 5. The post-STOP gate fires after the last STOP (review skills).
+  const gate = guard.staticInvariants.gateAfterStop;
+  if (gate) {
+    const firstStop = skeleton.indexOf(STOP);
+    const lastGate = skeleton.lastIndexOf(gate);
+    if (lastGate < 0) {
+      failures.push(`gateAfterStop marker missing from skeleton: "${gate}"`);
+    } else if (firstStop >= 0 && lastGate < firstStop) {
+      failures.push(`gateAfterStop "${gate}" appears before the STOP (stranded above it)`);
+    }
+  }
+
+  return failures;
+}
+
+/**
+ * Completeness (E1): the filesystem carved set must equal the registry set, both
+ * directions, and every registry entry must be internally consistent. Pure:
+ * takes `root`.
+ */
+export function checkCompleteness(root: string): string[] {
+  const failures: string[] = [];
+  const discovered = new Set(discoverCarvedSkills(root));
+  const registered = new Set(Object.keys(CARVE_GUARDS));
+
+  for (const skill of discovered) {
+    if (!registered.has(skill)) {
+      failures.push(`carved on disk but NOT in CARVE_GUARDS (unguarded carve): ${skill}`);
+    }
+  }
+  for (const skill of registered) {
+    if (!discovered.has(skill)) {
+      failures.push(`in CARVE_GUARDS but not carved on disk (stale registry entry): ${skill}`);
+    }
+  }
+
+  for (const [skill, g] of Object.entries(CARVE_GUARDS)) {
+    if (g.expectedSections.length === 0) {
+      failures.push(`${skill}: expectedSections is empty`);
+    }
+    if (g.requiredReads.length === 0) {
+      failures.push(`${skill}: requiredReads is empty (behavioral guard would be decorative)`);
+    }
+    for (const r of g.requiredReads) {
+      if (!g.expectedSections.includes(r)) {
+        failures.push(`${skill}: requiredRead "${r}" is not in expectedSections`);
+      }
+    }
+    // Behavioral guard exists: 'plan'/'prompt' are covered structurally by the
+    // data-driven loop (registry membership IS coverage); 'external' must name a
+    // dedicated test file that actually exists on disk.
+    if (g.behavioral === 'external') {
+      if (!g.externalTest) {
+        failures.push(`${skill}: behavioral 'external' but no externalTest path`);
+      } else if (!fs.existsSync(path.join(root, g.externalTest))) {
+        failures.push(`${skill}: externalTest missing on disk: ${g.externalTest}`);
+      }
+    }
+  }
+
+  return failures;
+}