fix(agent): detect symlink cycles in iter_skill_index_files to prevent infinite recursion

agent/skill_utils.py

@@ -701,9 +701,19 @@ def iter_skill_index_files(skills_dir: Path, filename: str):
     scripts) can contain arbitrary markdown and even archived package
     ``SKILL.md`` files, but they are progressive-disclosure data loaded through
     ``skill_view(..., file_path=...)`` rather than active skill roots.
+
+    Symlink cycles (e.g. ``skills/productivity/productivity -> ..``) are
+    detected via a *visited* set of resolved real paths.  When a cycle is
+    encountered the branch is pruned instead of recursing infinitely.
     """
     matches = []
+    visited: set = set()
     for root, dirs, files in os.walk(skills_dir, followlinks=True):
+        real_root = Path(root).resolve()
+        if real_root in visited:
+            dirs[:] = []  # prune this branch — already traversed
+            continue
+        visited.add(real_root)
         has_skill_md = "SKILL.md" in files
         dirs[:] = [
             d

tests/agent/test_skill_utils.py

@@ -215,7 +215,37 @@ def test_iter_skill_index_files_keeps_support_named_categories(tmp_path):
     assert is_excluded_skill_path(scripts_skill / "SKILL.md") is False
 
 
-# ── skill_matches_platform on Termux ──────────────────────────────────────
+def test_iter_skill_index_files_prunes_self_referencing_symlinks(tmp_path):
+    """Self-referencing symlinks must not cause infinite recursion.
+
+    Regression test for <https://github.com/NousResearch/hermes-agent/issues/47659>.
+    A symlink inside a skill directory that points back to its own parent
+    (e.g. ``productivity/productivity -> productivity/``) must be detected
+    as a cycle and pruned instead of recursing infinitely.
+    """
+    # Create a skill directory with a self-referencing symlink.
+    skill_dir = tmp_path / "productivity"
+    skill_dir.mkdir()
+    (skill_dir / "SKILL.md").write_text(
+        "---\nname: productivity\n---\n", encoding="utf-8"
+    )
+    # Symlink: productivity/productivity -> productivity/
+    (skill_dir / "productivity").symlink_to(skill_dir)
+
+    # Create a second skill without a cycle (control).
+    normal_skill = tmp_path / "research"
+    normal_skill.mkdir()
+    (normal_skill / "SKILL.md").write_text(
+        "---\nname: research\n---\n", encoding="utf-8"
+    )
+
+    found = list(iter_skill_index_files(tmp_path, "SKILL.md"))
+
+    # Each skill should appear exactly once — no duplicated entries from
+    # the cycle.
+    assert len(found) == 2
+    names = sorted(p.parent.name for p in found)
+    assert names == ["productivity", "research"]
 
 
 class TestSkillMatchesPlatformTermux: