messages = [
    {"role": "user", "content": "Sipariş ver: kahve makinesi İstanbul'a"},
 
    # Assistant: tool çağrısı yapar
    {
        "role": "assistant",
        "content": [
            {"type": "tool_use", "id": "tool_1", "name": "search_product", "input": {"q": "kahve makinesi"}}
        ],
    },
 
    # User: tool result döner
    {
        "role": "user",
        "content": [
            {
                "type": "tool_result",
                "tool_use_id": "tool_1",
                "content": "Bulunan ürünler: ...",  # ← bu kısım büyük olabilir
            }
        ],
    },
 
    # Assistant: bir sonraki tool
    {"role": "assistant", "content": [{"type": "tool_use", "name": "get_details", ...}]},
 
    # User: result
    {"role": "user", "content": [{"type": "tool_result", "tool_use_id": "tool_2", "content": "..."}]},
 
    # ... agent loop devam eder
]

def cache_recent_tool_result(messages, max_breakpoints=4):
    """Son N tool_result mesajına breakpoint koy (eski breakpoint'leri kaldır)."""
    # Tool_result mesajlarını bul
    tool_result_indices = [
        i for i, m in enumerate(messages)
        if isinstance(m.get("content"), list)
        and any(c.get("type") == "tool_result" for c in m["content"])
    ]
 
    # Sadece son max_breakpoints kadarına cache_control koy
    breakpoints_to_use = tool_result_indices[-max_breakpoints:]
 
    for i in breakpoints_to_use:
        messages[i]["content"][-1]["cache_control"] = {"type": "ephemeral", "ttl": "5m"}
 
    return messages