diff --git a/scripts/sync_extensions.py b/scripts/sync_extensions.py
index 0a6ccacc..040ff241 100644
--- a/scripts/sync_extensions.py
+++ b/scripts/sync_extensions.py
@@ -143,7 +143,8 @@ def collect_needed_commands() -> list[CommandSpec]:
             meta = parse_frontmatter(skill_md.read_text())
             desc = str(meta.get("description", ""))
             for trigger in slash_triggers(meta):
-                cmd_name = trigger.lstrip("/")
+                # Replace colons with dashes for cross-platform filename compatibility
+                cmd_name = trigger.lstrip("/").replace(":", "-")
                 cmd_path = skill_dir / "commands" / f"{cmd_name}.md"
                 needed.append(CommandSpec(path=cmd_path, trigger=trigger, description=desc))
     return needed
diff --git a/skills/github-pr-reviewer/commands/pr-reviewer:setup.md b/skills/github-pr-reviewer/commands/pr-reviewer-setup.md
similarity index 100%
rename from skills/github-pr-reviewer/commands/pr-reviewer:setup.md
rename to skills/github-pr-reviewer/commands/pr-reviewer-setup.md
diff --git a/skills/github-repo-monitor/commands/github-monitor:poll.md b/skills/github-repo-monitor/commands/github-monitor-poll.md
similarity index 100%
rename from skills/github-repo-monitor/commands/github-monitor:poll.md
rename to skills/github-repo-monitor/commands/github-monitor-poll.md
diff --git a/skills/incident-retrospective/commands/incident-retro:setup.md b/skills/incident-retrospective/commands/incident-retro-setup.md
similarity index 100%
rename from skills/incident-retrospective/commands/incident-retro:setup.md
rename to skills/incident-retrospective/commands/incident-retro-setup.md
diff --git a/skills/linear-triage/commands/linear-triage:setup.md b/skills/linear-triage/commands/linear-triage-setup.md
similarity index 100%
rename from skills/linear-triage/commands/linear-triage:setup.md
rename to skills/linear-triage/commands/linear-triage-setup.md
diff --git a/skills/openhands-automation/commands/automation:create.md b/skills/openhands-automation/commands/automation-create.md
similarity index 100%
rename from skills/openhands-automation/commands/automation:create.md
rename to skills/openhands-automation/commands/automation-create.md
diff --git a/skills/research-brief/commands/research-brief:setup.md b/skills/research-brief/commands/research-brief-setup.md
similarity index 100%
rename from skills/research-brief/commands/research-brief:setup.md
rename to skills/research-brief/commands/research-brief-setup.md
diff --git a/skills/slack-channel-monitor/commands/slack-monitor:poll.md b/skills/slack-channel-monitor/commands/slack-monitor-poll.md
similarity index 100%
rename from skills/slack-channel-monitor/commands/slack-monitor:poll.md
rename to skills/slack-channel-monitor/commands/slack-monitor-poll.md
diff --git a/skills/slack-standup-digest/commands/standup-digest:setup.md b/skills/slack-standup-digest/commands/standup-digest-setup.md
similarity index 100%
rename from skills/slack-standup-digest/commands/standup-digest:setup.md
rename to skills/slack-standup-digest/commands/standup-digest-setup.md
diff --git a/tests/test_sync_extensions.py b/tests/test_sync_extensions.py
index 6c7b5e67..8dfb703d 100644
--- a/tests/test_sync_extensions.py
+++ b/tests/test_sync_extensions.py
@@ -198,6 +198,20 @@ def test_paths_are_under_commands_dir(self):
             assert spec.path.parent.name == "commands"
             assert spec.path.suffix == ".md"
 
+    def test_colon_triggers_are_normalized_for_filenames(self, tmp_path, monkeypatch):
+        skill_dir = tmp_path / "skills" / "test-skill"
+        skill_dir.mkdir(parents=True)
+        (skill_dir / "SKILL.md").write_text(
+            "---\nname: test-skill\ndescription: Test\ntriggers:\n  - /test:command\n---\nBody\n"
+        )
+
+        monkeypatch.setattr("sync_extensions.SKILL_DIRS", [tmp_path / "skills"])
+
+        specs = collect_needed_commands()
+        assert [spec.path.relative_to(tmp_path).as_posix() for spec in specs] == [
+            "skills/test-skill/commands/test-command.md"
+        ]
+
 
 # ── load_marketplaces ────────────────────────────────────────────────