diff --git a/tests/tools/test_file_tools.py b/tests/tools/test_file_tools.py
index 3cc8ffa81e..a951ed25cb 100644
--- a/tests/tools/test_file_tools.py
+++ b/tests/tools/test_file_tools.py
@@ -366,44 +366,23 @@ class TestSearchHints:
 # ---------------------------------------------------------------------------
 
 class TestPatchSchemaShape:
-    """PATCH_SCHEMA must advertise per-mode required params so strict models
-    (e.g. kimi-k2.x) don't silently omit old_string / new_string for replace
-    mode, or patch content for patch mode."""
+    """PATCH_SCHEMA must advertise per-mode required params via description
+    text (not JSON-schema ``required``), so strict models like kimi-k2.x stop
+    silently omitting old_string / new_string / patch content."""
 
-    def test_required_only_contains_mode(self):
-        # anyOf is incompatible with several providers (Anthropic, Fireworks,
-        # Kimi/Moonshot). The only safe approach is description-level guidance.
-        assert PATCH_SCHEMA["parameters"]["required"] == ["mode"]
-
-    def test_top_level_description_documents_replace_mode_required_params(self):
+    def test_per_mode_required_params_documented_in_descriptions(self):
         desc = PATCH_SCHEMA["description"]
         assert "REQUIRED PARAMETERS: mode, path, old_string, new_string" in desc
-
-    def test_top_level_description_documents_patch_mode_required_params(self):
-        desc = PATCH_SCHEMA["description"]
         assert "REQUIRED PARAMETERS: mode, patch" in desc
+        props = PATCH_SCHEMA["parameters"]["properties"]
+        for name in ("path", "old_string", "new_string"):
+            assert "REQUIRED when mode='replace'" in props[name]["description"]
+        assert "REQUIRED when mode='patch'" in props["patch"]["description"]
 
-    def test_path_property_advertises_required_for_replace(self):
-        desc = PATCH_SCHEMA["parameters"]["properties"]["path"]["description"]
-        assert "REQUIRED when mode='replace'" in desc
-
-    def test_old_string_property_advertises_required_for_replace(self):
-        desc = PATCH_SCHEMA["parameters"]["properties"]["old_string"]["description"]
-        assert "REQUIRED when mode='replace'" in desc
-
-    def test_new_string_property_advertises_required_for_replace(self):
-        desc = PATCH_SCHEMA["parameters"]["properties"]["new_string"]["description"]
-        assert "REQUIRED when mode='replace'" in desc
-
-    def test_patch_property_advertises_required_for_patch_mode(self):
-        desc = PATCH_SCHEMA["parameters"]["properties"]["patch"]["description"]
-        assert "REQUIRED when mode='patch'" in desc
-
-    def test_no_anyof_at_parameters_level(self):
-        assert "anyOf" not in PATCH_SCHEMA["parameters"]
-        assert "oneOf" not in PATCH_SCHEMA["parameters"]
-
-    def test_schema_is_provider_compatible_object(self):
+    def test_no_anyof_required_stays_mode_only(self):
+        # anyOf/oneOf at parameters level break Anthropic, Fireworks, and the
+        # Moonshot/Kimi schema sanitizer — description-level guidance is the
+        # only provider-safe signalling mechanism.
         params = PATCH_SCHEMA["parameters"]
-        assert params["type"] == "object"
-        assert isinstance(params["properties"], dict)
+        assert params["required"] == ["mode"]
+        assert "anyOf" not in params and "oneOf" not in params