diff --git a/scripts/publish_test_metrics.py b/scripts/publish_test_metrics.py
index 82bc9c5..857555d 100755
--- a/scripts/publish_test_metrics.py
+++ b/scripts/publish_test_metrics.py
@@ -20,6 +20,10 @@ import xml.etree.ElementTree as ET
 from pathlib import Path
 
 
+SOURCE_SUFFIXES = {".go", ".py", ".js", ".mjs", ".ts", ".tsx", ".json", ".yaml", ".yml", ".sh"}
+SKIP_DIRS = {".git", ".venv", "venv", "node_modules", "build", "dist", "__pycache__", ".pytest_cache", "frontend-coverage"}
+
+
 def _escape_label(value: str) -> str:
     return value.replace("\\", "\\\\").replace("\n", "\\n").replace('"', '\\"')
 
@@ -106,6 +110,25 @@ def _load_gate_summary(path: Path) -> dict[str, object]:
         return {"ok": False, "issues": []}
 
 
+def _count_lines_over_limit(root: Path, *, max_lines: int = 500) -> int:
+    count = 0
+    for path in root.rglob("*"):
+        if not path.is_file():
+            continue
+        if any(part in SKIP_DIRS for part in path.parts):
+            continue
+        if path.name != "Jenkinsfile" and path.suffix.lower() not in SOURCE_SUFFIXES:
+            continue
+        try:
+            with path.open("r", encoding="utf-8", errors="ignore") as handle:
+                lines = sum(1 for _ in handle)
+        except OSError:
+            continue
+        if lines > max_lines:
+            count += 1
+    return count
+
+
 def _fetch_existing_counter(pushgateway_url: str, metric: str, labels: dict[str, str]) -> float:
     text = _read_http(f"{pushgateway_url.rstrip('/')}/metrics")
     if not text:
@@ -161,6 +184,7 @@ def main() -> int:
     backend_rc_file = Path(os.getenv("BACKEND_TEST_RC_FILE", "build/backend-test.rc"))
     frontend_rc_file = Path(os.getenv("FRONTEND_TEST_RC_FILE", "build/frontend-test.rc"))
     gate_summary = _load_gate_summary(Path(os.getenv("GATE_SUMMARY_FILE", "build/gate-summary.json")))
+    repo_root = Path(__file__).resolve().parents[1]
 
     b = _load_junit(backend_junit)
     f = _load_junit(frontend_junit)
@@ -175,6 +199,7 @@ def main() -> int:
     backend_pct = _load_backend_coverage_percent(backend_cov)
     frontend_pct = _load_frontend_coverage_percent(frontend_cov)
     coverage_pct = (backend_pct + frontend_pct) / 2 if (backend_pct or frontend_pct) else 0.0
+    over_500 = _count_lines_over_limit(repo_root)
 
     backend_rc = _read_test_exit_code(backend_rc_file)
     frontend_rc = _read_test_exit_code(frontend_rc_file)
@@ -219,6 +244,10 @@ def main() -> int:
         ok_count += 1
     else:
         failed_count += 1
+    tests_check = "ok" if outcome == "ok" else "failed"
+    coverage_check = "ok" if coverage_pct >= 95.0 else "failed"
+    loc_check = "ok" if over_500 == 0 else "failed"
+    gate_check = "ok" if gate_ok else "failed"
 
     payload_lines = [
         "# TYPE platform_quality_gate_runs_total counter",
@@ -238,6 +267,15 @@ def main() -> int:
         f'pegasus_quality_gate_status{{suite="{suite}",result="{"ok" if gate_ok else "failed"}"}} 1',
         "# TYPE pegasus_quality_gate_issues_total gauge",
         f'pegasus_quality_gate_issues_total{{suite="{suite}"}} {len(gate_issues)}',
+        "# TYPE platform_quality_gate_workspace_line_coverage_percent gauge",
+        f'platform_quality_gate_workspace_line_coverage_percent{{suite="{suite}"}} {coverage_pct:.3f}',
+        "# TYPE platform_quality_gate_source_lines_over_500_total gauge",
+        f'platform_quality_gate_source_lines_over_500_total{{suite="{suite}"}} {over_500}',
+        "# TYPE pegasus_quality_gate_checks_total gauge",
+        f'pegasus_quality_gate_checks_total{{suite="{suite}",check="tests",result="{tests_check}"}} 1',
+        f'pegasus_quality_gate_checks_total{{suite="{suite}",check="coverage",result="{coverage_check}"}} 1',
+        f'pegasus_quality_gate_checks_total{{suite="{suite}",check="loc",result="{loc_check}"}} 1',
+        f'pegasus_quality_gate_checks_total{{suite="{suite}",check="gate",result="{gate_check}"}} 1',
         "# TYPE pegasus_quality_gate_build_info gauge",
         f"pegasus_quality_gate_build_info{_label_str(labels)} 1",
     ]
@@ -254,6 +292,7 @@ def main() -> int:
         "tests_errors": totals["errors"],
         "tests_skipped": totals["skipped"],
         "coverage_percent": round(coverage_pct, 3),
+        "source_lines_over_500": over_500,
         "outcome": outcome,
         "backend_rc": backend_rc,
         "frontend_rc": frontend_rc,