Strip MiniCPM <think>...</think> reasoning tags from generated text

llm/zerogpu_backend.py

@@ -142,11 +142,28 @@ def _generate_on_gpu(
 
     new_tokens = outputs[0][inputs["input_ids"].shape[1]:]
     text = _tokenizer.decode(new_tokens, skip_special_tokens=True).strip()
+    text = _strip_think_tags(text)
     if json_mode:
         text = _extract_json(text)
     return text
 
 
+_THINK_TAG_RE = None
+
+
+def _strip_think_tags(text: str) -> str:
+    """Remove <think>...</think> blocks (incl. empty ones) that MiniCPM4 and
+    other hybrid-reasoning models emit even when /no_think is present in the
+    system prompt. Also strips a stray opening/closing tag if unmatched."""
+    import re
+    global _THINK_TAG_RE
+    if _THINK_TAG_RE is None:
+        _THINK_TAG_RE = re.compile(r"<think>.*?</think>\s*", re.DOTALL | re.IGNORECASE)
+    cleaned = _THINK_TAG_RE.sub("", text)
+    cleaned = re.sub(r"</?think>\s*", "", cleaned, flags=re.IGNORECASE)
+    return cleaned.strip()
+
+
 def _extract_json(text: str) -> str:
     cleaned = text.strip()
     if cleaned.startswith("```"):