diff --git a/CHANGELOG.md b/CHANGELOG.md
index f5f7bb2..967a478 100644
Binary files a/CHANGELOG.md and b/CHANGELOG.md differ
diff --git a/src/schemaforge/check.py b/src/schemaforge/check.py
index f69a2b5..0f82245 100644
--- a/src/schemaforge/check.py
+++ b/src/schemaforge/check.py
@@ -73,7 +73,7 @@ def check_directory(
             failures.append(f"  FAIL {name}: {e}")
 
     if not converted:
-        return "No files could be converted to {}\n{}".format(
+        return "FAIL: No files could be converted to {}\n{}".format(
             canonical, "\n".join(failures)
         )
 
@@ -109,10 +109,18 @@ def check_directory(
         lines.append("")
         for m in mismatches:
             lines.append(m)
-        lines.append("FAIL: Schema files are not equivalent")
+
+    # Deterministic exit-status lines. The CLI keys its process exit code off
+    # these. A conversion failure must fail the check even when there is no
+    # pairwise mismatch -- previously the "Mismatches: 0" report with no PASS
+    # line let CI report green while a schema silently failed to parse.
+    if mismatches or failures:
+        if mismatches:
+            lines.append("FAIL: Schema files are not equivalent")
+        if failures:
+            lines.append(f"FAIL: {len(failures)} file(s) failed to convert")
     else:
         lines.append("  Mismatches: 0")
-        if not failures:
-            lines.append("PASS: All schema files are equivalent")
+        lines.append("PASS: All schema files are equivalent")
 
     return "\n".join(lines)
diff --git a/src/schemaforge/cli.py b/src/schemaforge/cli.py
index ce984d4..a011f2d 100644
--- a/src/schemaforge/cli.py
+++ b/src/schemaforge/cli.py
@@ -177,7 +177,7 @@ def check(directory: str, canonical: str, type_map_path: str | None) -> None:
     try:
         result = check_directory(directory, canonical=canonical, type_map_path=type_map_path)
         click.echo(result)
-        if "FAIL" in result and "PASS" not in result:
+        if "FAIL:" in result:
             sys.exit(1)
     except (NotADirectoryError, ValueError, FileNotFoundError) as e:
         click.echo(f"Error: {e}", err=True)
diff --git a/tests/test_check.py b/tests/test_check.py
index 1030e1b..f8382be 100644
--- a/tests/test_check.py
+++ b/tests/test_check.py
@@ -138,3 +138,20 @@ def test_check_directory_canonical_format():
 
         result = check_directory(tmpdir, canonical="prisma")
         assert "compared via prisma" in result
+
+
+def test_check_directory_conversion_failure_reports_fail():
+    """A file that fails to parse must produce a FAIL line (not a silent PASS).
+
+    Regression guard: previously a conversion failure with no pairwise mismatch
+    yielded "Mismatches: 0" and no PASS/FAIL line, so the CLI exited 0 (green)
+    while a schema silently failed to parse.
+    """
+    with tempfile.TemporaryDirectory() as tmpdir:
+        Path(tmpdir, "schema.sql").write_text(SAMPLE_SQL)
+        Path(tmpdir, "broken.json").write_text("{ this is not valid json ,,, }")
+
+        result = check_directory(tmpdir)
+        assert "Conversion failures: 1" in result
+        assert "FAIL: 1 file(s) failed to convert" in result
+        assert "PASS:" not in result
diff --git a/tests/test_cli.py b/tests/test_cli.py
index ddaecaa..b5ed620 100644
--- a/tests/test_cli.py
+++ b/tests/test_cli.py
@@ -509,10 +509,35 @@ def test_check_invalid_directory(self):
         finally:
             Path(f_path).unlink(missing_ok=True)
 
+    def test_check_cli_exits_nonzero_on_conversion_failure(self):
+        """Regression: a schema that fails to parse must make `check` exit non-zero.
+
+        Previously the CLI only failed on mismatches, so a parse failure with no
+        pairwise mismatch reported "Mismatches: 0" and exited 0 (silent green).
+        """
+        runner = CliRunner()
+        with tempfile.TemporaryDirectory() as tmpdir:
+            Path(tmpdir, "schema.sql").write_text(SAMPLE_SQL)
+            Path(tmpdir, "broken.json").write_text("{ this is not valid json ,,, }")
+
+            result = runner.invoke(main, ["check", "--dir", tmpdir])
+            assert result.exit_code != 0
+            assert "FAIL:" in result.output
+
+    def test_check_cli_exits_zero_when_all_equivalent(self):
+        """Two identical schema files are trivially equivalent -> exit 0 with PASS."""
+        runner = CliRunner()
+        with tempfile.TemporaryDirectory() as tmpdir:
+            Path(tmpdir, "a.sql").write_text(SAMPLE_SQL)
+            Path(tmpdir, "b.sql").write_text(SAMPLE_SQL)
+
+            result = runner.invoke(main, ["check", "--dir", tmpdir])
+            assert result.exit_code == 0
+            assert "PASS: All schema files are equivalent" in result.output
+
 
 # ═══════════════════════════════════════════════════════════════
 #  mcp command
-# ═══════════════════════════════════════════════════════════════
 
 
 class TestMcpCommand: