{
 "note": "Output-token change split into a tokenizer part and a verbosity part by counting the same answer texts with each model tokenizer (free count_tokens endpoint). The per-request overhead of the endpoint was measured per model with a one-character message and subtracted; counts are therefore close approximations, and the combined figure is compared with the provider-reported change.",
 "overheadTokens": {
  "claude-opus-4-6": 7,
  "claude-opus-4-7": 11,
  "claude-opus-4-8": 6,
  "claude-opus-5-5": 8,
  "claude-sonnet-4-6": 7,
  "claude-sonnet-5-5": 8,
  "claude-haiku-4-5-20251001": 7,
  "claude-haiku-5-5": 8
 },
 "steps": [
  {
   "from": "claude-opus-4-6",
   "to": "claude-opus-4-7",
   "answersCompared": 60,
   "tokenizerEffectPct": 41.8,
   "verbosityEffectPct": -11.35,
   "combinedPct": 25.7,
   "reportedOutputTokenChangePct": 25.76
  },
  {
   "from": "claude-opus-4-7",
   "to": "claude-opus-4-8",
   "answersCompared": 60,
   "tokenizerEffectPct": 0,
   "verbosityEffectPct": -1.13,
   "combinedPct": -1.14,
   "reportedOutputTokenChangePct": -1.49
  },
  {
   "from": "claude-opus-4-6",
   "to": "claude-opus-5-5",
   "answersCompared": 60,
   "tokenizerEffectPct": 41.8,
   "verbosityEffectPct": 39.59,
   "combinedPct": 97.93,
   "reportedOutputTokenChangePct": 139.88
  },
  {
   "from": "claude-sonnet-4-6",
   "to": "claude-sonnet-5-5",
   "answersCompared": 60,
   "tokenizerEffectPct": 42.76,
   "verbosityEffectPct": -1.66,
   "combinedPct": 40.39,
   "reportedOutputTokenChangePct": 57.34
  },
  {
   "from": "claude-haiku-4-5-20251001",
   "to": "claude-haiku-5-5",
   "answersCompared": 60,
   "tokenizerEffectPct": 45.08,
   "verbosityEffectPct": 28.77,
   "combinedPct": 86.81,
   "reportedOutputTokenChangePct": 137.46
  }
 ]
}