diff --git a/aria-brain/agent.py b/aria-brain/agent.py
index 0038e90..2474131 100644
--- a/aria-brain/agent.py
+++ b/aria-brain/agent.py
@@ -787,10 +787,18 @@ def _skill_to_tool(s: dict) -> dict:
         }
         if a.get("required"):
             required.append(name)
+    # Tool-Namen duerfen in der Anthropic/Claude tool_use-API nur
+    # [a-zA-Z0-9_-]{1,64} sein, aber der claude-max-api-proxy (OpenAI-
+    # Format-Adapter) ist restriktiver und faellt bei Bindestrichen auf
+    # die Nase — die GANZE Tool-Liste wird dann verworfen und ARIA
+    # bekommt "No such tool available". Skill-Namen wie 'yt-dlp-download'
+    # oder 'pdf-umfrage-generator' muessen daher zu run_yt_dlp_download
+    # bzw. run_pdf_umfrage_generator gemappt werden.
+    safe_name = "run_" + re.sub(r"[^a-zA-Z0-9_]", "_", s["name"])
     return {
         "type": "function",
         "function": {
-            "name": f"run_{s['name']}",
+            "name": safe_name,
             "description": s.get("description", "(ohne Beschreibung)"),
             "parameters": {
                 "type": "object",
@@ -844,7 +852,7 @@ class Agent:
         count = ev["count"]
         migration_key = f"auto/skill-bypass/{skill_name}"
         title = f"Skill '{skill_name}' nutzen, nicht curl"
-        run_tool = f"run_{skill_name.replace('-', '_')}"
+        run_tool = "run_" + re.sub(r"[^a-zA-Z0-9_]", "_", skill_name)
         content = (
             f"WICHTIG fuer Performance + Stefans Wartezeit: "
             f"Skill '{skill_name}' existiert und deckt {host} ab. "
@@ -1262,7 +1270,18 @@ class Agent:
                     f"Sicherheits-Snapshot des vorherigen Stands: {res.get('safety_snapshot')}"
                 )
             if name.startswith("run_"):
-                skill_name = name[len("run_"):]
+                # Tool-Namen sind 'safe' (nur _), Skill-Namen koennen aber
+                # Bindestriche enthalten (z.B. yt-dlp-download). Wir suchen
+                # zuerst exakt, dann ueber Underscore-zu-Bindestrich-Mapping.
+                tool_suffix = name[len("run_"):]
+                skill_name = tool_suffix
+                if skills_mod.read_manifest(skill_name) is None:
+                    # ggf. Bindestriche zurueckmappen
+                    for cand in skills_mod.list_skills(active_only=False):
+                        cand_name = cand.get("name") or ""
+                        if re.sub(r"[^a-zA-Z0-9_]", "_", cand_name) == tool_suffix:
+                            skill_name = cand_name
+                            break
                 res = skills_mod.run_skill(skill_name, args=arguments)
                 snippet = (res.get("stdout") or "")[:2000] or "(kein stdout)"
                 err = (res.get("stderr") or "")[:500]
diff --git a/aria-brain/api_heuristic.py b/aria-brain/api_heuristic.py
index 3fa6492..dd23a95 100644
--- a/aria-brain/api_heuristic.py
+++ b/aria-brain/api_heuristic.py
@@ -164,8 +164,9 @@ def build_bypass_section(bypass_events: list[dict]) -> str:
         sname = ev["skill_name"]
         host = ev["host"]
         count = ev["count"]
+        safe = re.sub(r"[^a-zA-Z0-9_]", "_", sname)
         lines.append(f"- gegen **{host}** ({count}x kuerzlich) → nutze "
-                     f"`run_{sname.replace('-', '_')}(...)` statt curl. "
+                     f"`run_{safe}(...)` statt curl. "
                      f"Der Skill ist da. Nutze ihn.")
     lines.append("")
     return "\n".join(lines)