Fix tool extraction: raw JSON decode for Qwen3 plain output

app.py

@@ -101,10 +101,26 @@ def _execute_tool(name: str, args: dict) -> str:
         return f"Tool error: {type(e).__name__}: {e}"
 
 def _extract_tool_calls(text: str):
+    """Extract JSON tool calls from LLM output.
+    Handles: raw JSON,  blocks, embedded JSON objects."""
     calls = []
+    # Method 1:  blocks (legacy format)
     for m in re.finditer(r'', text, re.DOTALL):
         try: calls.append(json.loads(m.group(1).strip()))
         except: pass
+    if calls:
+        return calls
+    # Method 2: Raw JSON objects anywhere in text (Qwen3 outputs plain JSON)
+    decoder = json.JSONDecoder()
+    pos = 0
+    while pos < len(text):
+        try:
+            obj, end = decoder.raw_decode(text, pos)
+            if isinstance(obj, dict) and "name" in obj and "arguments" in obj:
+                calls.append(obj)
+            pos = end
+        except json.JSONDecodeError:
+            pos += 1
     return calls
 
 def _dispatch_tool_calls(calls: list):