diff --git a/scripts/ci/opencode_review_normalize_output.py b/scripts/ci/opencode_review_normalize_output.py
index c7cbeb63..c6cc0450 100755
--- a/scripts/ci/opencode_review_normalize_output.py
+++ b/scripts/ci/opencode_review_normalize_output.py
@@ -315,21 +315,26 @@ def mentions_changed_file_evidence(reason: str, summary: str) -> bool:
     return bool(CHANGED_FILE_EVIDENCE_PATTERN.search(f"{reason}\n{summary}"))
 
 
-def current_changed_files() -> set[str]:
-    """Return the exact current-head changed files when the workflow provides them."""
+def current_changed_files() -> set[str] | None:
+    """Return the exact current-head changed files when the workflow provides them, or None if unavailable."""
     changed_files_path = os.environ.get("OPENCODE_CHANGED_FILES_FILE")
     if not changed_files_path:
-        return set()
+        return None
+
+    path = Path(changed_files_path)
+    if not path.is_file():
+        return None
+
     try:
         return {
             line.strip()
-            for line in Path(changed_files_path)
+            for line in path
             .read_text(encoding="utf-8")
             .splitlines()
             if line.strip()
         }
     except OSError:
-        return set()
+        return None
 
 
 def changed_file_is_source_like(path: str) -> bool:
@@ -404,8 +409,10 @@ def contradicts_material_changed_file_scope(reason: str, summary: str) -> bool:
 def mentions_actual_changed_file(reason: str, summary: str) -> bool:
     """Return whether an approval names an exact current-head changed file."""
     changed_files = current_changed_files()
-    if not changed_files:
+    if changed_files is None:
         return mentions_changed_file_evidence(reason, summary)
+    if not changed_files:
+        return True
     combined = f"{reason}\n{summary}"
     return any(changed_file in combined for changed_file in changed_files)
 
@@ -572,13 +579,18 @@ def build_approval_repair_summary(summary: str, evidence_text: str) -> str | Non
     """Append missing approval labels from bounded current-head evidence."""
     changed_files = changed_files_from_evidence(evidence_text)
     coverage_mode = evidence_coverage_mode(evidence_text)
-    if not changed_files or coverage_mode is None:
+    if coverage_mode is None:
         return None
 
-    first_file = changed_files[0]
-    file_list = ", ".join(changed_files[:5])
-    if len(changed_files) > 5:
-        file_list += f", and {len(changed_files) - 5} more"
+    if not changed_files:
+        first_file = "no-files-changed"
+        file_list = "no files changed"
+    else:
+        first_file = changed_files[0]
+        file_list = ", ".join(changed_files[:5])
+        if len(changed_files) > 5:
+            file_list += f", and {len(changed_files) - 5} more"
+
     if coverage_mode == "not_applicable":
         coverage_line = (
             "Coverage: coverage execution evidence reports test coverage as not applicable "
diff --git a/tests/test_opencode_review_normalize_output.py b/tests/test_opencode_review_normalize_output.py
index fcc7d37d..b7e3ac54 100644
--- a/tests/test_opencode_review_normalize_output.py
+++ b/tests/test_opencode_review_normalize_output.py
@@ -92,7 +92,7 @@ def test_changed_file_and_verification_posture_detection():
 
 def test_actual_changed_file_detection_prefers_current_head_file_list(tmp_path, monkeypatch):
     monkeypatch.delenv("OPENCODE_CHANGED_FILES_FILE", raising=False)
-    assert norm.current_changed_files() == set()
+    assert norm.current_changed_files() is None
     assert norm.mentions_actual_changed_file("scripts/ci/example.py", "")
 
     changed_files = tmp_path / "changed-files.txt"
@@ -126,9 +126,27 @@ def test_actual_changed_file_detection_prefers_current_head_file_list(tmp_path,
     )
 
     monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(tmp_path / "missing.txt"))
-    assert norm.current_changed_files() == set()
+    assert norm.current_changed_files() is None
     assert norm.mentions_actual_changed_file("scripts/ci/example.py", "")
 
+    empty_files = tmp_path / "empty-files.txt"
+    empty_files.write_text("", encoding="utf-8")
+    monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(empty_files))
+    assert norm.current_changed_files() == set()
+    assert norm.mentions_actual_changed_file("No files changed", "Empty PR")
+
+    dir_path = tmp_path / "a_directory"
+    dir_path.mkdir()
+    monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(dir_path))
+    assert norm.current_changed_files() is None
+
+    def raise_os_error(*args, **kwargs):
+        raise OSError("Permission denied")
+
+    monkeypatch.setattr(norm.Path, "read_text", raise_os_error)
+    monkeypatch.setenv("OPENCODE_CHANGED_FILES_FILE", str(changed_files))
+    assert norm.current_changed_files() is None
+
 
 def test_preferred_review_language_handles_unreadable_and_unknown_evidence(tmp_path, monkeypatch):
     evidence = tmp_path / "evidence.md"
@@ -485,6 +503,29 @@ def test_valid_control_filters_shape_head_and_review_contract():
 
 
 def test_valid_control_repairs_approval_summary_from_bounded_evidence(tmp_path, monkeypatch):
+    evidence = tmp_path / "bounded-review-evidence-empty.md"
+    evidence.write_text(
+        """\
+# OpenCode bounded PR review evidence
+
+## Coverage execution evidence
+
+# Coverage Evidence
+
+## Coverage Decision
+
+- Result: PASS
+- Test coverage: not applicable because no supported changed source files or package manifests were found.
+- Docstring coverage: not applicable
+
+## Changed files
+""",
+        encoding="utf-8",
+    )
+    monkeypatch.setenv("OPENCODE_EVIDENCE_FILE", str(evidence))
+    monkeypatch.delenv("OPENCODE_CHANGED_FILES_FILE", raising=False)
+    assert norm.build_approval_repair_summary("", evidence.read_text(encoding="utf-8")) is not None
+
     evidence = tmp_path / "bounded-review-evidence.md"
     evidence.write_text(
         """\