fix(cli): normalize malformed skills config in get_disabled_skills (#61797)

skills: null crashed with AttributeError, and a bare scalar
disabled: my-skill was split into a set of characters. Both now
normalize the same way agent.skill_utils._normalize_string_set does:
null -> empty set, scalar -> single-item set. Non-dict skills
sections are ignored.

Closes #13026.

hermes_cli/skills_config.py

@@ -24,6 +24,23 @@ PLATFORMS = {k: info.label for k, info in _PLATFORMS.items() if k != "api_server
 
 # ─── Config Helpers ───────────────────────────────────────────────────────────
 
+def _normalize_skill_names(values) -> Set[str]:
+    """Normalize a config value into a set of skill names.
+
+    Mirrors ``agent.skill_utils._normalize_string_set``: ``None`` (YAML null)
+    means empty, a bare scalar (``disabled: my-skill``) means a single-item
+    list — NOT a set of its characters (#13026).
+    """
+    if values is None:
+        return set()
+    if isinstance(values, str):
+        values = [values]
+    try:
+        return {str(v).strip() for v in values if str(v).strip()}
+    except TypeError:
+        return set()
+
+
 def get_disabled_skills(config: dict, platform: Optional[str] = None) -> Set[str]:
     """Return disabled skill names: the global list unioned with the
     platform-specific list when a platform is given.
@@ -32,14 +49,16 @@ def get_disabled_skills(config: dict, platform: Optional[str] = None) -> Set[str
     platform list adds to the global list rather than replacing it. This
     mirrors ``agent.skill_utils.get_disabled_skill_names``.
     """
-    skills_cfg = config.get("skills", {})
-    global_disabled = set(skills_cfg.get("disabled", []))
+    skills_cfg = config.get("skills") or {}
+    if not isinstance(skills_cfg, dict):
+        return set()
+    global_disabled = _normalize_skill_names(skills_cfg.get("disabled"))
     if platform is None:
         return global_disabled
     platform_disabled = cfg_get(skills_cfg, "platform_disabled", platform)
     if platform_disabled is None:
         return global_disabled
-    return global_disabled | set(platform_disabled)
+    return global_disabled | _normalize_skill_names(platform_disabled)
 
 
 def save_disabled_skills(config: dict, disabled: Set[str], platform: Optional[str] = None):

tests/hermes_cli/test_skills_config.py

@@ -46,6 +46,34 @@ class TestGetDisabledSkills:
         from hermes_cli.skills_config import get_disabled_skills
         assert get_disabled_skills({"other": "value"}) == set()
 
+    def test_null_skills_section(self):
+        """``skills:`` with no value (YAML null) must not crash (#13026)."""
+        from hermes_cli.skills_config import get_disabled_skills
+        assert get_disabled_skills({"skills": None}) == set()
+        assert get_disabled_skills({"skills": None}, platform="telegram") == set()
+
+    def test_null_disabled_key(self):
+        from hermes_cli.skills_config import get_disabled_skills
+        assert get_disabled_skills({"skills": {"disabled": None}}) == set()
+
+    def test_scalar_disabled_is_single_skill_not_characters(self):
+        """``disabled: my-skill`` (bare scalar) is one skill name, not a
+        set of its characters (#13026)."""
+        from hermes_cli.skills_config import get_disabled_skills
+        assert get_disabled_skills({"skills": {"disabled": "my-skill"}}) == {"my-skill"}
+
+    def test_scalar_platform_disabled(self):
+        from hermes_cli.skills_config import get_disabled_skills
+        config = {"skills": {
+            "disabled": ["global-skill"],
+            "platform_disabled": {"telegram": "tg-skill"},
+        }}
+        assert get_disabled_skills(config, platform="telegram") == {"global-skill", "tg-skill"}
+
+    def test_non_dict_skills_section(self):
+        from hermes_cli.skills_config import get_disabled_skills
+        assert get_disabled_skills({"skills": "oops"}) == set()
+
     def test_empty_disabled_list(self):
         from hermes_cli.skills_config import get_disabled_skills
         assert get_disabled_skills({"skills": {"disabled": []}}) == set()