从一个 while 循环开始，一步步搭出完整的 Agent

code/py/01_agent_loop.py · 01 / 04# code/py/01_agent_loop.py — Agent 循环闭环@dataclassclass LoopState:    messages: list    turn_count: int = 1    transition_reason: str | None = None def run_turn(state: LoopState) -> bool:    response = client.chat.completions.create(        model=model,        messages=[{"role": "system", "content": SYSTEM_PROMPT},                  *state.messages],        tools=TOOLS,        max_completion_tokens=8000,    )    choice = response.choices[0]    message = choice.message    state.messages.append({        "role": "assistant",        "content": message.content or "",        "tool_calls": serialize_tool_calls(message.tool_calls),    })    if choice.finish_reason != "tool_calls":        return False                       # ← 模型说完了，退出    state.messages.extend(execute_tool_calls(message.tool_calls))    state.turn_count += 1    return True                            # ← 还有工具要跑，继续 def agent_loop(state: LoopState) -> None:    while run_turn(state):        pass