{
  "status": "measured",
  "measured_at": "2026-09-17T08:33:46Z",
  "model": "gpt-6-astra",
  "sample_size": 3,
  "input_tokens": 8613,
  "cached_input_tokens": 5710,
  "requests_with_cache": 2,
  "cache_read_price_ratio": 0.1,
  "cache_write_price_ratio": 1.25,
  "requests": [
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  "methodology":"合成固定前缀，3 次普通请求与 3 次固定前缀显式缓存请求；优化组包含首次写入。读取 Responses 完成事件的 usage，不缓存回复。",
  "note":"受控小样本，不代表全站或日常命中率；输出与未命中输入另计费，缓存写入也有费用。"
}