diff --git a/tests/test_audit_dataclass_coverage.py b/tests/test_audit_dataclass_coverage.py
new file mode 100644
index 00000000..bd445382
--- /dev/null
+++ b/tests/test_audit_dataclass_coverage.py
@@ -0,0 +1,98 @@
+"""Tests for scripts/audit_dataclass_coverage.py
+
+The audit counts `dict[str, Any]` and `list[dict[...]]` annotations that
+remain outside the 5 promoted dataclass sites (mcp_tool_specs, openai_schemas,
+provider_state, log_registry.Session, api_hooks.WebSocketMessage).
+
+Mirrors tests/test_audit_weak_types.py structure.
+
+CONVENTION: 1-space indentation. NO COMMENTS.
+"""
+from __future__ import annotations
+
+import json
+import subprocess
+import sys
+from pathlib import Path
+
+import pytest
+
+
+REPO_ROOT = Path(__file__).resolve().parents[1]
+AUDIT_SCRIPT = REPO_ROOT / "scripts" / "audit_dataclass_coverage.py"
+BASELINE_FILE = REPO_ROOT / "scripts" / "audit_dataclass_coverage.baseline.json"
+
+
+def _run_audit(*args: str) -> subprocess.CompletedProcess[str]:
+ return subprocess.run(
+  [sys.executable, str(AUDIT_SCRIPT), *args],
+  cwd=str(REPO_ROOT),
+  capture_output=True,
+  text=True,
+  timeout=60,
+ )
+
+
+def test_audit_script_exists() -> None:
+ assert AUDIT_SCRIPT.is_file(), f"audit script missing: {AUDIT_SCRIPT}"
+
+
+def test_audit_help_runs() -> None:
+ result = _run_audit("--help")
+ assert result.returncode == 0
+ assert "audit" in result.stdout.lower()
+
+
+def test_audit_json_mode_emits_valid_json() -> None:
+ result = _run_audit("--json")
+ assert result.returncode == 0, f"audit --json failed: {result.stderr}"
+ payload = json.loads(result.stdout)
+ assert "files_scanned" in payload
+ assert "total_weak" in payload
+ assert "by_category" in payload
+ assert isinstance(payload["total_weak"], int)
+ assert payload["total_weak"] >= 0
+
+
+def test_audit_default_mode_emits_human_report() -> None:
+ result = _run_audit()
+ assert result.returncode == 0, f"audit default mode failed: {result.stderr}"
+ assert "Dataclass Coverage Audit" in result.stdout or "dataclass" in result.stdout.lower()
+
+
+def test_audit_strict_mode_against_existing_baseline_passes() -> None:
+ if not BASELINE_FILE.is_file():
+  pytest.skip("baseline not yet generated; skip --strict assertion")
+ result = _run_audit("--strict", "--baseline", str(BASELINE_FILE))
+ assert result.returncode == 0, (
+  f"audit --strict failed (current count > baseline): {result.stderr}"
+ )
+ assert "STRICT OK" in result.stdout
+
+
+def test_audit_strict_mode_fails_when_baseline_is_zero() -> None:
+ tmp_baseline = REPO_ROOT / "tests" / "artifacts" / "tier2_state" / "any_type_componentization_20260621" / "_zero_baseline.json"
+ tmp_baseline.parent.mkdir(parents=True, exist_ok=True)
+ tmp_baseline.write_text(json.dumps({"total_weak": 0}), encoding="utf-8")
+ try:
+  result = _run_audit("--strict", "--baseline", str(tmp_baseline))
+  assert result.returncode == 1, "audit --strict should fail when current > baseline=0"
+  assert "STRICT" in result.stderr or "regression" in result.stderr.lower()
+ finally:
+  if tmp_baseline.exists():
+   tmp_baseline.unlink()
+
+
+def test_audit_baseline_field_shape() -> None:
+ result = _run_audit("--json")
+ assert result.returncode == 0
+ payload = json.loads(result.stdout)
+ assert "total_weak" in payload
+ assert "files_with_findings" in payload
+ assert "by_category" in payload
+ assert "by_file" in payload
+ assert isinstance(payload["by_file"], list)
+ if payload["by_file"]:
+  entry = payload["by_file"][0]
+  assert "filename" in entry
+  assert "weak_count" in entry
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