diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index 88ae94031..5d993634a 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -1301,6 +1301,14 @@ jobs:
         shell: bash
         run: bash scripts/verify/tests/verify-vulnerability-gates.Tests.sh
 
+      - name: Self-test gosec gate (fail-closed contract)
+        shell: bash
+        run: bash scripts/verify/tests/verify-gosec-gates.Tests.sh
+
+      - name: Self-test secret guard (fail-closed contract)
+        shell: bash
+        run: bash scripts/verify/tests/check-secrets.Tests.sh
+
       - name: Verify Web Hub-only boundary
         run: python scripts/verify/verify-web-hub-boundary.py
 
diff --git a/scripts/verify/tests/check-secrets.Tests.sh b/scripts/verify/tests/check-secrets.Tests.sh
new file mode 100644
index 000000000..84808a8d9
--- /dev/null
+++ b/scripts/verify/tests/check-secrets.Tests.sh
@@ -0,0 +1,104 @@
+#!/usr/bin/env bash
+# Self-tests for check-secrets.sh — fail-closed secret guard contract.
+#
+# Positive: placeholder values, *.env.example files, and *_URL endpoint
+# assignments pass.
+# Negative: real AWS keys, GitHub tokens, private key blocks, and API keys
+# (sk-...) in staged diffs must ALL exit non-zero.
+#
+# Runs in CI validate job alongside verify-vulnerability-gates.Tests.sh.
+set -uo pipefail
+
+SCRIPT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)/check-secrets.sh"
+PASS=0
+FAIL=0
+
+check() {
+  local name="$1" expect_fail="$2" actual="$3"
+  if { [[ "$expect_fail" == "yes" ]] && [[ "$actual" -ne 0 ]]; } || \
+     { [[ "$expect_fail" == "no" ]] && [[ "$actual" -eq 0 ]]; }; then
+    echo "  PASS  $name (exit=$actual)"
+    PASS=$((PASS + 1))
+  else
+    echo "  FAIL  $name (exit=$actual, expected $([[ "$expect_fail" == "yes" ]] && echo "!=0" || echo "0"))"
+    FAIL=$((FAIL + 1))
+  fi
+}
+
+# Create a temp git repo so check-secrets.sh has a git root to scan.
+TMP_REPO="$(mktemp -d)"
+trap 'rm -rf "$TMP_REPO"' EXIT
+cd "$TMP_REPO"
+git init --quiet
+git config user.email "test@example.com"
+git config user.name "Test"
+
+echo "=== empty worktree (no changes) ==="
+bash "$SCRIPT" --worktree >/dev/null 2>&1
+check "empty worktree exits 0" no $?
+
+echo "=== placeholder .env.example passes ==="
+cat > .env.example <<'ENV'
+AGENTHUB_TOKENDANCE_ID_CLIENT_SECRET=your-client-secret-here
+AGENTHUB_HUB_JWT_SECRET=change-me-in-production
+ENV
+git add .env.example
+bash "$SCRIPT" --staged >/dev/null 2>&1
+check "placeholder .env.example passes" no $?
+
+echo "=== *_URL endpoint assignment passes ==="
+cat > config.yaml <<'YAML'
+AGENTHUB_TOKENDANCE_ID_ISSUER_URL=https://id.example.com
+AGENTHUB_TOKENDANCE_ID_REDIRECT_URI=https://hub.example.com/client/auth/callback
+YAML
+git add config.yaml
+git commit --quiet -m "add config" 2>/dev/null
+# Now stage a new change with a URL assignment
+echo 'AGENTHUB_WEB_URL=https://web.example.com' >> config.yaml
+git add config.yaml
+bash "$SCRIPT" --staged >/dev/null 2>&1
+check "*_URL endpoint assignment passes" no $?
+
+echo "=== real AWS access key fails ==="
+git reset --quiet
+cat > secrets.yaml <<'YAML'
+aws_access_key_id: AKIAIOSFODNN7EXAMPLE
+YAML
+git add secrets.yaml
+bash "$SCRIPT" --staged >/dev/null 2>&1
+check "AWS access key fails" yes $?
+
+echo "=== GitHub token fails ==="
+git reset --quiet
+cat > gh-token.json <<'JSON'
+{"token": "ghp_1234567890abcdefghijklmnopqrstuvwxyzABCD"}
+JSON
+git add gh-token.json
+bash "$SCRIPT" --staged >/dev/null 2>&1
+check "GitHub token fails" yes $?
+
+echo "=== private key block fails ==="
+git reset --quiet
+cat > key.pem <<'PEM'
+-----BEGIN RSA PRIVATE KEY-----
+MIIEpAIBAAKCAQEA1234567890abcdefghijklmnopqrstuvwxyz
+-----END RSA PRIVATE KEY-----
+PEM
+git add key.pem
+bash "$SCRIPT" --staged >/dev/null 2>&1
+check "private key file path fails" yes $?
+
+echo "=== API key (sk-) fails ==="
+git reset --quiet
+cat > api.yaml <<'YAML'
+openai_api_key: sk-proj-1234567890abcdefghijklmnopqrstuvwxyz
+YAML
+git add api.yaml
+bash "$SCRIPT" --staged >/dev/null 2>&1
+check "sk- API key fails" yes $?
+
+echo ""
+echo "Results: $PASS passed, $FAIL failed"
+if [[ "$FAIL" -gt 0 ]]; then
+  exit 1
+fi
diff --git a/scripts/verify/verify-ci-gates.py b/scripts/verify/verify-ci-gates.py
index ffcebef59..bdc9cf359 100644
--- a/scripts/verify/verify-ci-gates.py
+++ b/scripts/verify/verify-ci-gates.py
@@ -132,6 +132,8 @@ def main() -> int:
     assert_contains(vuln_go, re.escape("verify-vulnerability-gates.sh govulncheck"), "vuln-scan-go must run the fail-closed govulncheck verifier")
     assert_contains(vuln_js, re.escape("verify-vulnerability-gates.sh pnpm-audit"), "vuln-scan-js must run the fail-closed pnpm audit verifier")
     assert_contains(validate, r"Self-test vulnerability gates", "validate must self-test the vulnerability gates")
+    assert_contains(validate, r"Self-test gosec gate", "validate must self-test the gosec fail-closed contract")
+    assert_contains(validate, r"Self-test secret guard", "validate must self-test the secret guard fail-closed contract")
 
     # Native Windows is a compatibility contract, not a duplicate release
     # pipeline: backend and frontend matrix legs must remain path-filtered and