diff --git a/dependabot_file.py b/dependabot_file.py
index f69251a..8e8c814 100644
--- a/dependabot_file.py
+++ b/dependabot_file.py
@@ -28,6 +28,29 @@
 )
 VALID_COOLDOWN_DAYS_KEYS = frozenset(COOLDOWN_DAYS_KEYS_ORDERED)
 VALID_COOLDOWN_KEYS = VALID_COOLDOWN_DAYS_KEYS | {"include", "exclude"}
+SEMVER_COOLDOWN_ECOSYSTEMS = frozenset(
+    {
+        "bundler",
+        "bun",
+        "cargo",
+        "composer",
+        "conda",
+        "dotnet-sdk",
+        "elm",
+        "gomod",
+        "gradle",
+        "julia",
+        "maven",
+        "mix",
+        "npm",
+        "nuget",
+        "pip",
+        "pub",
+        "rust-toolchain",
+        "swift",
+        "uv",
+    }
+)
 MAX_COOLDOWN_LIST_ITEMS = 150
 MIN_COOLDOWN_DAYS = 1
 MAX_COOLDOWN_DAYS = 90
@@ -171,14 +194,17 @@ def make_dependabot_config(
     if cooldown:
         cooldown_config = {}
         for key in COOLDOWN_DAYS_KEYS_ORDERED:
-            if key in cooldown:
+            if key in cooldown and (
+                key == "default-days" or ecosystem in SEMVER_COOLDOWN_ECOSYSTEMS
+            ):
                 cooldown_config[key] = cooldown[key]
-        for list_key in ("include", "exclude"):
-            if list_key in cooldown:
-                cooldown_config[list_key] = [
-                    SingleQuotedScalarString(item) for item in cooldown[list_key]
-                ]
-        dependabot_config["updates"][-1].update({"cooldown": cooldown_config})
+        if cooldown_config:
+            for list_key in ("include", "exclude"):
+                if list_key in cooldown:
+                    cooldown_config[list_key] = [
+                        SingleQuotedScalarString(item) for item in cooldown[list_key]
+                    ]
+            dependabot_config["updates"][-1].update({"cooldown": cooldown_config})
 
 
 def build_dependabot_file(
diff --git a/test_dependabot_file.py b/test_dependabot_file.py
index 218be0a..f3f5285 100644
--- a/test_dependabot_file.py
+++ b/test_dependabot_file.py
@@ -862,8 +862,8 @@ def test_build_dependabot_file_with_cooldown_default_days_only(self):
         )
         self.assertEqual(result, expected_result)
 
-    def test_build_dependabot_file_with_cooldown_all_params(self):
-        """Test that cooldown with all semver day parameters is added correctly"""
+    def test_build_dependabot_file_filters_unsupported_semver_cooldown_params(self):
+        """Test that ecosystems without SemVer cooldown support only get default-days"""
         repo = MagicMock()
         repo.get_contents.side_effect = lambda filename: filename == "Dockerfile" or []
 
@@ -882,15 +882,92 @@ def test_build_dependabot_file_with_cooldown_all_params(self):
       interval: 'weekly'
     cooldown:
       default-days: 3
-      semver-major-days: 7
-      semver-minor-days: 3
-      semver-patch-days: 1
 """)
         result = build_dependabot_file(
             repo, False, [], {}, None, "weekly", "", [], None, cooldown
         )
         self.assertEqual(result, expected_result)
 
+    def test_build_dependabot_file_filters_github_actions_semver_cooldown_params(self):
+        """Test that GitHub Actions keeps general cooldown fields but not SemVer fields"""
+        repo = MagicMock()
+        workflow_file = MagicMock()
+        workflow_file.name = "test.yml"
+
+        def get_contents(path):
+            if path == "package.json":
+                return True
+            if path == ".github/workflows":
+                return [workflow_file]
+            return []
+
+        repo.get_contents.side_effect = get_contents
+        cooldown = {
+            "default-days": 7,
+            "semver-major-days": 14,
+            "semver-minor-days": 7,
+            "semver-patch-days": 3,
+            "exclude": ["critical-package"],
+        }
+        expected_result = yaml.load(b"""
+version: 2
+updates:
+  - package-ecosystem: 'npm'
+    directory: '/'
+    schedule:
+      interval: 'weekly'
+    cooldown:
+      default-days: 7
+      semver-major-days: 14
+      semver-minor-days: 7
+      semver-patch-days: 3
+      exclude:
+        - 'critical-package'
+  - package-ecosystem: 'github-actions'
+    directory: '/'
+    schedule:
+      interval: 'weekly'
+    cooldown:
+      default-days: 7
+      exclude:
+        - 'critical-package'
+""")
+
+        result = build_dependabot_file(
+            repo, False, [], {}, None, "weekly", "", [], None, cooldown
+        )
+
+        self.assertEqual(result, expected_result)
+
+    def test_build_dependabot_file_omits_unsupported_semver_only_cooldown(self):
+        """Test that GitHub Actions omits cooldown when no supported day field remains"""
+        repo = MagicMock()
+        workflow_file = MagicMock()
+        workflow_file.name = "test.yml"
+        repo.get_contents.side_effect = lambda path: (
+            [workflow_file] if path == ".github/workflows" else []
+        )
+        cooldown = {
+            "semver-major-days": 14,
+            "semver-minor-days": 7,
+            "semver-patch-days": 3,
+            "exclude": ["critical-package"],
+        }
+        expected_result = yaml.load(b"""
+version: 2
+updates:
+  - package-ecosystem: 'github-actions'
+    directory: '/'
+    schedule:
+      interval: 'weekly'
+""")
+
+        result = build_dependabot_file(
+            repo, False, [], {}, None, "weekly", "", [], None, cooldown
+        )
+
+        self.assertEqual(result, expected_result)
+
     def test_build_dependabot_file_with_cooldown_include_exclude(self):
         """Test that cooldown with include/exclude lists is added correctly"""
         repo = MagicMock()