_TOOL_USE_BLOCK_RE = re.compile(
    r"<tool_use>\s*(\{.*?\})\s*</tool_use>", re.DOTALL
)

---

<tool_use>{"id": "t1", "name": "terminal", "input": {"command": "ls -la", "timeout": 300}}</tool_use>

---

{"id": "t1", "name": "terminal", "input": {"command": "ls -la"

---

def _extract_tool_uses_from_text(text: str) -> tuple[list[SimpleNamespace], str]:
    """Pull <tool_use>{...}</tool_use> blocks out with proper nested brace handling."""
    if not isinstance(text, str) or "<tool_use>" not in text:
        return [], text or ""
    
    blocks: list[SimpleNamespace] = []
    spans: list[tuple[int, int]] = []
    
    pos = 0
    while True:
        start_tag = text.find("<tool_use>", pos)
        if start_tag == -1:
            break
        json_start = start_tag + len("<tool_use>")
        while json_start < len(text) and text[json_start].isspace():
            json_start += 1
        
        brace_count = 0
        json_end = json_start
        in_string = False
        escape_next = False
        
        for i in range(json_start, len(text)):
            ch = text[i]
            if escape_next:
                escape_next = False
                continue
            if ch == '\\':
                escape_next = True
                continue
            if ch == '"' and not escape_next:
                in_string = not in_string
                continue
            if not in_string:
                if ch == '{':
                    brace_count += 1
                elif ch == '}':
                    brace_count -= 1
                    if brace_count == 0:
                        json_end = i + 1
                        break
        
        if brace_count != 0:
            pos = start_tag + 1
            continue
        
        end_tag_start = text.find("</tool_use>", json_end)
        if end_tag_start == -1:
            pos = start_tag + 1
            continue
        
        raw = text[json_start:json_end]
        try:
            obj = json.loads(raw)
        except Exception:
            pos = end_tag_start + len("</tool_use>")
            continue
        
        name = obj.get("name")
        if not isinstance(name, str) or not name.strip():
            pos = end_tag_start + len("</tool_use>")
            continue
        call_id = obj.get("id")
        if not isinstance(call_id, str) or not call_id.strip():
            call_id = f"toolu_cli_{uuid.uuid4().hex[:16]}"
        input_data = obj.get("input")
        if not isinstance(input_data, dict):
            input_data = {}
        blocks.append(_tool_use_block(call_id, name.strip(), input_data))
        spans.append((start_tag, end_tag_start + len("</tool_use>")))
        pos = end_tag_start + len("</tool_use>")
    
    if not spans:
        return blocks, text
    parts: list[str] = []
    cursor = 0
    for start, end in spans:
        if cursor < start:
            parts.append(text[cursor:start])
        cursor = max(cursor, end)
    if cursor < len(text):
        parts.append(text[cursor:])
    return blocks, "".join(parts).strip()

---

def test_nested_json_tool_use():
    text = '<tool_use>{"id":"t1","name":"terminal","input":{"command":"ls","timeout":300}}</tool_use>'
    blocks, leftover = _extract_tool_uses_from_text(text)
    assert len(blocks) == 1
    assert blocks[0].name == "terminal"
    assert blocks[0].input == {"command": "ls", "timeout": 300}
    assert leftover == ""