diff --git a/services/hwfit/models.py b/services/hwfit/models.py
index 6f2bb00e7..c042c9462 100644
--- a/services/hwfit/models.py
+++ b/services/hwfit/models.py
@@ -145,7 +145,7 @@ def is_prequantized(model):
         or re.search(r"(^|[-_/])fp8($|[-_/\s])", text) is not None
         or (not (model.get("is_gguf") or model.get("gguf_sources")) and re.search(r"(^|[-_/])(?:int)?8bit($|[-_/\s])", text) is not None)
         or any(x in text for x in ("awq", "gptq", "mlx"))
-        or any(q.startswith(p) for p in PREQUANTIZED_PREFIXES)
+        or any(isinstance(q, str) and q.startswith(p) for p in PREQUANTIZED_PREFIXES)
     )
 
 
@@ -155,7 +155,7 @@ def params_b(model):
         return raw / 1_000_000_000.0
 
     pc = model.get("parameter_count", "")
-    if pc:
+    if isinstance(pc, str) and pc:
         pc = pc.strip().upper()
         m = re.match(r"^([\d.]+)\s*([BKMGT]?)$", pc)
         if m:
diff --git a/tests/test_hwfit_models_nonstring_fields.py b/tests/test_hwfit_models_nonstring_fields.py
new file mode 100644
index 000000000..9bd234aca
--- /dev/null
+++ b/tests/test_hwfit_models_nonstring_fields.py
@@ -0,0 +1,31 @@
+"""Harden hwfit model-catalog parsing against non-string field values.
+
+`params_b` and `is_prequantized` read free-form fields straight off the HF
+catalog JSON. `parameter_count` is normally a string like "7B" and
+`quantization` a string like "FP8", but a catalog row can carry a non-string
+(e.g. an integer parameter_count, or a null/number quantization). The code
+called `pc.strip()` / `q.startswith(...)` directly, so one such row raised
+AttributeError and aborted the whole ranking pass (params_b/is_prequantized
+run for every model). Non-strings are now treated as unknown.
+"""
+from services.hwfit.models import params_b, is_prequantized
+
+
+def test_params_b_nonstring_count_does_not_raise():
+    assert params_b({"parameter_count": 7}) == 0.0
+    assert params_b({"parameter_count": ["7B"]}) == 0.0
+
+
+def test_params_b_valid_count_still_parses():
+    assert params_b({"parameter_count": "7B"}) == 7.0
+    assert params_b({"parameters_raw": 7_000_000_000}) == 7.0
+
+
+def test_is_prequantized_nonstring_quantization_does_not_raise():
+    assert is_prequantized({"quantization": 8}) is False
+    assert is_prequantized({"name": "plain-model", "quantization": 123}) is False
+
+
+def test_is_prequantized_still_detects_real_markers():
+    assert is_prequantized({"name": "some-model-awq"}) is True
+    assert is_prequantized({"quantization": "FP8-Mixed"}) is True