diff --git a/.github/workflows/apm-audit.yml b/.github/workflows/apm-audit.yml
index ce39d99..8404b7b 100644
--- a/.github/workflows/apm-audit.yml
+++ b/.github/workflows/apm-audit.yml
@@ -2,20 +2,23 @@ name: apm-audit
 
 # Reusable workflow shipped by zava-agent-config for downstream APM consumers.
 #
-# v5.1.0+: the reusable workflow now runs `apm audit --ci --policy org`
-# explicitly. v5.0.x called microsoft/apm-action with audit-report only,
-# which generated SARIF but did NOT enforce the org policy or fail the
-# job on violations — drift-only check, no policy gate. This regression
-# was caught during the D2 governance demo wiring (see DevExpGbb/.github
-# apm-policy.yml v2.0.0) where required-packages, dependency-denylist,
-# and unmanaged-files violations passed CI silently.
+# v5.1.2: switched apm-action to setup-only and removed `apm install` from
+# the audit path. Reason: install RE-DEPLOYS files from upstream, OVERWRITING
+# any in-PR tamper of a deployed managed file. That silently disabled drift
+# detection in CI (caught during D2 demo Beat 5 wiring). Audit now runs
+# directly against the contents of the PR, so content-integrity / drift /
+# unmanaged-files all see what the PR author committed.
+#
+# v5.1.1: auto-detect repo apm-policy.yml override and use it as policy
+# source so `extends: org` actually layers (vs --policy org which loads
+# only the org layer).
+#
+# v5.1.0: explicit `apm audit --ci --policy ...` — the apm-action default
+# only generates SARIF and does not enforce policy.
 #
 #   jobs:
 #     audit:
-#       uses: DevExpGbb/zava-agent-config/.github/workflows/apm-audit.yml@v5.1.0
-#
-# Pinning the workflow to a tag means the consumer's audit step is part of
-# the supply chain they audit — no implicit "latest" reusable workflow.
+#       uses: DevExpGbb/zava-agent-config/.github/workflows/apm-audit.yml@v5.1.2
 
 on:
   workflow_call:
@@ -49,26 +52,18 @@ jobs:
             echo "::notice::No APM dependencies declared — audit is a no-op."
           fi
 
-      # Install + run apm install via the action. setup-only would skip install,
-      # but we WANT install to also run so policy enforcement at install time
-      # (denylist on uninstalled new deps) catches violations even before audit.
-      - name: Install APM + dependencies
+      # setup-only installs the apm CLI on PATH and skips `apm install`.
+      # We must NOT run install here: it would re-deploy primitives from
+      # upstream and overwrite any tampered file in the PR, masking drift.
+      - name: Install APM CLI
         if: steps.detect.outputs.has_deps == 'true'
         uses: microsoft/apm-action@v1
         with:
-          audit-report: true
+          setup-only: true
 
-      # Explicit policy enforcement. The action generates SARIF but does NOT
-      # call `--ci` or `--policy` — it runs drift-only. This step closes the
-      # gap: `--policy org` resolves the consumer org's apm-policy.yml from
-      # GitHub (DevExpGbb/.github/apm-policy.yml in our case) and `--ci`
-      # makes block-enforcement violations exit non-zero.
-      # Detect repo-level override. apm policy supports tighten-only override
-      # layering via `extends: org` in a repo apm-policy.yml. When present,
-      # use the repo file as policy source so the audit gates on the EFFECTIVE
-      # policy (org ∪ repo override). Falls back to `--policy org` otherwise.
       - name: Detect repo policy override
         id: policy
+        if: steps.detect.outputs.has_deps == 'true'
         run: |
           if [ -f apm-policy.yml ]; then
             echo "source=./apm-policy.yml" >> "$GITHUB_OUTPUT"
@@ -77,32 +72,29 @@ jobs:
             echo "source=org" >> "$GITHUB_OUTPUT"
           fi
 
-      - name: Enforce APM policy (org + repo override)
+      - name: Enforce APM policy + drift (apm audit --ci)
         if: steps.detect.outputs.has_deps == 'true'
         env:
-          GITHUB_APM_PAT: ${{ github.token }}
           APM_FAIL_ON_WARN: ${{ inputs.fail-on-warn }}
           POLICY_SOURCE: ${{ steps.policy.outputs.source }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         run: |
-          set -e
+          set -euo pipefail
           if [ "$APM_FAIL_ON_WARN" = "true" ]; then
-            apm audit --ci --policy "$POLICY_SOURCE" --fail-on-warn
+            apm audit --ci --policy "$POLICY_SOURCE" --fail-on-warning
           else
             apm audit --ci --policy "$POLICY_SOURCE"
           fi
 
-      - name: Summarize on PR
-        if: always() && github.event_name == 'pull_request'
+      - name: Step summary
+        if: always() && steps.detect.outputs.has_deps == 'true'
         run: |
           {
-            echo "## 🛡️ APM Audit"
+            echo "## APM audit"
+            echo ""
+            echo "- Policy source: \`${{ steps.policy.outputs.source }}\`"
+            echo "- Layered enforcement: repo override (\`extends: org\`) when present, else org floor"
+            echo "- Checks: lockfile-exists, ref-consistency, deployed-files-present, no-orphaned-packages, skill-subset-consistency, config-consistency, content-integrity, drift, required-packages, dependency-allowlist, dependency-denylist, unmanaged-files"
             echo ""
-            if [ "${{ steps.detect.outputs.has_deps }}" = "true" ]; then
-              echo "Ran \`apm audit --ci --policy org\` against the consumer's org policy via \`microsoft/apm-action@v1\`."
-              echo "(Org policy resolved from \`<consumer-org>/.github/apm-policy.yml\` automatically.)"
-              echo ""
-              echo "SARIF report uploaded by apm-action; see job logs and Code scanning tab."
-            else
-              echo "No APM dependencies declared in \`apm.yml\` — audit skipped."
-            fi
+            echo "Ran \`apm audit --ci --policy $POLICY_SOURCE\` against PR contents (no \`apm install\` — drift detection sees the as-committed file state)."
           } >> "$GITHUB_STEP_SUMMARY"