diff --git a/internal/scaffold/fullsend-repo/scripts/post-review-test.sh b/internal/scaffold/fullsend-repo/scripts/post-review-test.sh
index 7301542a2..3cce03f83 100644
--- a/internal/scaffold/fullsend-repo/scripts/post-review-test.sh
+++ b/internal/scaffold/fullsend-repo/scripts/post-review-test.sh
@@ -85,7 +85,8 @@ run_test "reject-label" \
   "reject" "false" "rejected"
 
 # Defensive: comment + downgraded=true can't occur in production (DOWNGRADED is
-# only set inside the approve branch), but verify the label logic handles it.
+# only set inside the approve branch, by either the protected-path or
+# governance-document downgrade path), but verify the label logic handles it.
 run_test "comment-with-downgrade-flag" \
   "comment" "true" "requires-manual-review"
 
@@ -99,6 +100,96 @@ run_test "failure-action-no-label" \
 run_test "unknown-action-no-label" \
   "banana" "false" "none"
 
+# ---------------------------------------------------------------------------
+# Governance document detection — reimplements the loop from post-review.sh
+# to verify all-governance vs mixed-file classification.
+# ---------------------------------------------------------------------------
+GOVERNANCE_DOC_PATTERNS=(
+  "MAINTAINERS.md"
+  "GOVERNANCE.md"
+  "CODE_OF_CONDUCT.md"
+  "SECURITY.md"
+)
+
+is_all_governance() {
+  local pr_files="$1"
+  local all_gov=true
+  while IFS= read -r file; do
+    [ -z "${file}" ] && continue
+    local base
+    base=$(basename "${file}")
+    local is_gov=false
+    for pattern in "${GOVERNANCE_DOC_PATTERNS[@]}"; do
+      if [ "${base}" = "${pattern}" ]; then
+        is_gov=true
+        break
+      fi
+    done
+    if [ "${is_gov}" = "false" ]; then
+      all_gov=false
+      break
+    fi
+  done <<< "${pr_files}"
+  echo "${all_gov}"
+}
+
+run_gov_test() {
+  local test_name="$1"
+  local pr_files="$2"
+  local expected="$3"
+
+  local actual
+  actual="$(is_all_governance "${pr_files}")"
+
+  if [ "${actual}" != "${expected}" ]; then
+    echo "FAIL: ${test_name}"
+    echo "  files:    '${pr_files}'"
+    echo "  expected: '${expected}'"
+    echo "  actual:   '${actual}'"
+    FAILURES=$((FAILURES + 1))
+    return
+  fi
+
+  echo "PASS: ${test_name}"
+}
+
+# --- Governance detection test cases ---
+
+# All governance files → downgrade
+run_gov_test "all-governance-single" \
+  "GOVERNANCE.md" "true"
+
+run_gov_test "all-governance-multiple" \
+  "GOVERNANCE.md
+MAINTAINERS.md
+CODE_OF_CONDUCT.md" "true"
+
+# Governance files in subdirectories → still governance
+run_gov_test "governance-in-subdir" \
+  "docs/GOVERNANCE.md
+community/CODE_OF_CONDUCT.md" "true"
+
+# Mixed: governance + non-governance → no downgrade
+run_gov_test "mixed-files-no-downgrade" \
+  "GOVERNANCE.md
+src/main.go" "false"
+
+# Non-governance only → no downgrade
+run_gov_test "non-governance-only" \
+  "src/main.go
+README.md" "false"
+
+# Substring mismatch: MY_GOVERNANCE.md is not a governance doc
+run_gov_test "substring-no-match" \
+  "MY_GOVERNANCE.md" "false"
+
+# All four governance patterns
+run_gov_test "all-four-patterns" \
+  "MAINTAINERS.md
+GOVERNANCE.md
+CODE_OF_CONDUCT.md
+SECURITY.md" "true"
+
 # --- Summary ---
 
 echo ""
diff --git a/internal/scaffold/fullsend-repo/scripts/post-review.sh b/internal/scaffold/fullsend-repo/scripts/post-review.sh
index 955c64de1..0fa208394 100755
--- a/internal/scaffold/fullsend-repo/scripts/post-review.sh
+++ b/internal/scaffold/fullsend-repo/scripts/post-review.sh
@@ -4,9 +4,10 @@
 # Runs on the GitHub Actions runner AFTER the sandbox is destroyed.
 # CWD is runDir.
 #
-# This script is the sole enforcement point for protected-path checks:
-# if the PR touches sensitive paths, an "approve" action is downgraded
-# to "comment" so only a human can grant approval.
+# This script is the sole enforcement point for protected-path and
+# governance-document checks: if the PR touches sensitive paths or
+# consists solely of governance documents, an "approve" action is
+# downgraded to "comment" so only a human can grant approval.
 #
 # Required environment variables:
 #   REVIEW_TOKEN    — token with pull-requests:write on the target repo
@@ -90,6 +91,11 @@ REVIEW_PROTECTED_PATHS=(
   "skills/"
 )
 
+# Temp files used by downgrade paths below; cleaned up on exit.
+MODIFIED_RESULT=""
+GOV_RESULT=""
+trap 'rm -f "${MODIFIED_RESULT}" "${GOV_RESULT}"' EXIT
+
 DOWNGRADED=false
 if [ "${ACTION}" = "approve" ]; then
   PR_FILES=$(gh pr view "${PR_NUMBER}" --repo "${REPO_FULL_NAME}" --json files --jq '.files[].path')
@@ -126,13 +132,61 @@ if [ "${ACTION}" = "approve" ]; then
 
     # Rewrite the result file with downgraded action and appended notice.
     MODIFIED_RESULT=$(mktemp)
-    trap 'rm -f "${MODIFIED_RESULT}"' EXIT
     jq --arg notice "${PROTECTED_NOTICE}" \
       '.action = "comment" | .body = (.body + $notice)' \
       "${RESULT_FILE}" > "${MODIFIED_RESULT}"
     RESULT_FILE="${MODIFIED_RESULT}"
     DOWNGRADED=true
   fi
+
+  # -------------------------------------------------------------------------
+  # Governance-document check: if ALL changed files are governance docs,
+  # downgrade "approve" to "comment" (defense-in-depth, mirrors the
+  # protected-path downgrade above).
+  # Governance document patterns (kept in sync with pr-review SKILL.md):
+  # -------------------------------------------------------------------------
+  if [ "${DOWNGRADED}" = "false" ]; then
+    GOVERNANCE_DOC_PATTERNS=(
+      "MAINTAINERS.md"
+      "GOVERNANCE.md"
+      "CODE_OF_CONDUCT.md"
+      "SECURITY.md"
+    )
+
+    ALL_GOVERNANCE=true
+    while IFS= read -r file; do
+      [ -z "${file}" ] && continue
+      BASENAME=$(basename "${file}")
+      IS_GOV=false
+      for pattern in "${GOVERNANCE_DOC_PATTERNS[@]}"; do
+        if [ "${BASENAME}" = "${pattern}" ]; then
+          IS_GOV=true
+          break
+        fi
+      done
+      if [ "${IS_GOV}" = "false" ]; then
+        ALL_GOVERNANCE=false
+        break
+      fi
+    done <<< "${PR_FILES}"
+
+    if [ "${ALL_GOVERNANCE}" = "true" ]; then
+      echo "All changed files are governance documents — downgrading approve to comment"
+
+      GOV_NOTICE=$'\n\n---\n\n'
+      GOV_NOTICE+=$'> **Governance documents detected** — all changed files in this PR are\n'
+      GOV_NOTICE+=$'> governance or process documents. The review agent cannot approve PRs that\n'
+      GOV_NOTICE+=$'> consist solely of governance documents.\n'
+      GOV_NOTICE+=$'> A human reviewer must approve this PR.\n'
+
+      GOV_RESULT=$(mktemp)
+      jq --arg notice "${GOV_NOTICE}" \
+        '.action = "comment" | .body = (.body + $notice)' \
+        "${RESULT_FILE}" > "${GOV_RESULT}"
+      RESULT_FILE="${GOV_RESULT}"
+      DOWNGRADED=true
+    fi
+  fi
 fi
 
 # ---------------------------------------------------------------------------
diff --git a/internal/scaffold/fullsend-repo/skills/pr-review/SKILL.md b/internal/scaffold/fullsend-repo/skills/pr-review/SKILL.md
index a0ecf414b..893810991 100644
--- a/internal/scaffold/fullsend-repo/skills/pr-review/SKILL.md
+++ b/internal/scaffold/fullsend-repo/skills/pr-review/SKILL.md
@@ -627,6 +627,57 @@ attention.
 If no protected files are modified, do not add a `protected-path`
 finding.
 
+##### Governance document check
+
+Check whether the PR modifies **only** governance or process documents.
+Governance documents define organizational policy — who has authority,
+how it is granted, codes of conduct — whose correctness is a human
+judgment call about organizational values. The agent evaluates these
+documents for formatting, link validity, and consistency, but cannot
+assess whether the policy itself is sound.
+
+Governance document patterns (kept in sync with `post-review.sh`):
+
+- `MAINTAINERS.md`
+- `GOVERNANCE.md`
+- `CODE_OF_CONDUCT.md`
+- `SECURITY.md`
+
+These patterns match files with the given name in any directory (e.g.,
+`docs/GOVERNANCE.md` matches). Matching is case-sensitive and compares
+exact filenames, not substrings — `MY_GOVERNANCE.md` does not match.
+The governance file list may be extended per-repo via `AGENTS.md` or
+`CLAUDE.md` configuration.
+
+If **all** changed files match governance document patterns, add an
+**info**-level finding. The description MUST list the matched
+governance files:
+
+```json
+{
+  "severity": "info",
+  "category": "governance-document",
+  "file": "N/A",
+  "description": "All changed files are governance documents (<list matched files>). Governance documents define organizational policy and require human review. Agent findings are informational only.",
+  "actionable": false
+}
+```
+
+When a `governance-document` finding is present, the outcome MUST be
+capped at `comment` — never `approve`. The agent's sub-agent findings
+(formatting, links, consistency) are still included as informational
+comments, but the verdict does not signal merge-readiness.
+
+If the PR modifies governance documents **alongside** non-governance
+files (source code, tests, configuration), the governance-document
+check does NOT trigger. The PR follows the normal review flow — the
+governance files are reviewed as part of the full change set.
+
+If a governance document also falls under a protected path (e.g.,
+`.github/GOVERNANCE.md`), both the `governance-document` and
+`protected-path` checks may fire independently. Both converge on
+blocking approval, so there is no conflict.
+
 #### 6f. Determine overall outcome
 
 Merge PR-specific findings into the challenger-adjudicated finding set
@@ -640,7 +691,10 @@ and evaluate:
   block the PR)
 - **Low** or **info** findings only (no medium+) → `approve` (attach
   findings as comments; preserve concrete follow-up work with
-  `actionable: true` so the post-script can create follow-up issues)
+  `actionable: true` so the post-script can create follow-up issues).
+  **Exception:** if a `protected-path` or `governance-document`
+  finding is present, the outcome is capped at `comment` regardless
+  of severity — see the constraints below.
 - No findings → `approve`
 - The approach is fundamentally wrong — wrong design, unauthorized
   change, or the PR should be closed/completely rethought → `reject`.
@@ -782,10 +836,12 @@ wins.
   `request-changes`.
 - **Never approve when any protected-path finding exists**, regardless of
   severity.
+- **Never approve when a governance-document finding exists.** If all
+  changed files are governance documents, the outcome must be `comment`.
 - **PR-specific checks (step 6e) belong in the orchestrator only.** Do
-  not push protected-path checks, scope authorization, or PR body
-  injection defense into sub-agents. These require PR-level context
-  that sub-agents do not have.
+  not push protected-path checks, governance-document checks, scope
+  authorization, or PR body injection defense into sub-agents. These
+  require PR-level context that sub-agents do not have.
 - **All sub-agents must be dispatched simultaneously.** Include all
   Agent calls in a single message. Sequential dispatch defeats the
   architecture's purpose.