fix(moa): tolerate non-numeric values in hand-edited MoA preset config

_normalize_preset uses bare float() and int() to coerce
reference_temperature, aggregator_temperature, and max_tokens from
config.yaml.  When a user hand-edits a non-numeric value (e.g.
max_tokens: "8k" or reference_temperature: "hot"), the coercion raises
ValueError.  Since normalize_moa_config runs on every model-selection
and MoA turn (via resolve_moa_preset), the crash is unrecoverable and
blocks all MoA usage until the config is manually fixed.

Replace the bare casts with _coerce_float / _coerce_int helpers that
fall back to the default on TypeError/ValueError instead of raising.

hermes_cli/moa_config.py

@@ -21,6 +21,27 @@ DEFAULT_MOA_AGGREGATOR: dict[str, str] = {
 }
 
 
+def _coerce_float(value: Any, default: float) -> float:
+    if value is None or value == "":
+        return default
+    try:
+        return float(value)
+    except (TypeError, ValueError):
+        return default
+
+
+def _coerce_int(value: Any, default: int) -> int:
+    if value is None or value == "":
+        return default
+    try:
+        return int(value)
+    except (TypeError, ValueError):
+        try:
+            return int(float(value))
+        except (TypeError, ValueError):
+            return default
+
+
 def _clean_slot(slot: Any) -> dict[str, str] | None:
     if not isinstance(slot, dict):
         return None
@@ -57,9 +78,9 @@ def _normalize_preset(raw: Any) -> dict[str, Any]:
         "enabled": bool(raw.get("enabled", True)),
         "reference_models": refs,
         "aggregator": aggregator,
-        "reference_temperature": float(raw.get("reference_temperature", 0.6) or 0.6),
-        "aggregator_temperature": float(raw.get("aggregator_temperature", 0.4) or 0.4),
-        "max_tokens": int(raw.get("max_tokens", 4096) or 4096),
+        "reference_temperature": _coerce_float(raw.get("reference_temperature"), 0.6),
+        "aggregator_temperature": _coerce_float(raw.get("aggregator_temperature"), 0.4),
+        "max_tokens": _coerce_int(raw.get("max_tokens"), 4096),
     }
 
 

tests/hermes_cli/test_moa_config.py

@@ -55,6 +55,45 @@ def test_legacy_flat_config_becomes_default_preset():
     ]
 
 
+def test_normalize_moa_config_tolerates_non_numeric_values():
+    """Non-numeric strings in hand-edited config.yaml must degrade to defaults
+    instead of crashing normalize_moa_config with ValueError."""
+    cfg = normalize_moa_config(
+        {
+            "presets": {
+                "broken": {
+                    "max_tokens": "notanumber",
+                    "reference_temperature": "hot",
+                    "aggregator_temperature": "",
+                }
+            }
+        }
+    )
+
+    preset = cfg["presets"]["broken"]
+    assert preset["max_tokens"] == 4096
+    assert preset["reference_temperature"] == 0.6
+    assert preset["aggregator_temperature"] == 0.4
+
+
+def test_normalize_moa_config_coerces_numeric_strings():
+    """Valid numeric strings (e.g. from YAML round-trip) must coerce correctly."""
+    cfg = normalize_moa_config({"max_tokens": "8192", "reference_temperature": "0.9"})
+
+    preset = cfg["presets"][DEFAULT_MOA_PRESET_NAME]
+    assert preset["max_tokens"] == 8192
+    assert preset["reference_temperature"] == 0.9
+
+
+def test_normalize_moa_config_coerces_float_max_tokens():
+    """max_tokens: 4096.0 (float from YAML) must coerce to int."""
+    cfg = normalize_moa_config({"max_tokens": 4096.0})
+    assert cfg["presets"][DEFAULT_MOA_PRESET_NAME]["max_tokens"] == 4096
+
+    cfg2 = normalize_moa_config({"max_tokens": "4096.5"})
+    assert cfg2["presets"][DEFAULT_MOA_PRESET_NAME]["max_tokens"] == 4096
+
+
 def test_exact_preset_matching_is_not_fuzzy():
     config = {"presets": {"coding": {}, "review": {}}}