{
 "note": "Append-only price and benchmark history for benchr models. Each entry is a snapshot of one model at a point in time. Do NOT backfill historical data — only add verified entries from the day you verify them. Format: add a new object to the 'snapshots' array. Never edit or delete existing entries.",
 "append_format": {
  "fields": {
   "date": "YYYY-MM-DD (required)",
   "model_id": "matches models.json id field (required)",
   "model_name": "human-readable model name (required)",
   "event": "one of: price_change | new_model | benchmark_update | deprecation_announced | sunset | context_change",
   "pricing": "{ input_per_million, output_per_million } — omit if unchanged",
   "context_max_tokens": "new context window size — omit if unchanged",
   "benchmarks": "{ key: value } — omit if unchanged",
   "note": "one-line description of what changed and the official source"
  },
  "example": {
   "date": "2026-07-01",
   "model_id": "gpt-5-5",
   "model_name": "GPT-5.5",
   "event": "price_change",
   "pricing": {
    "input_per_million": 4.0,
    "output_per_million": 25.0
   },
   "note": "OpenAI reduced GPT-5.5 pricing. Source: openai.com/pricing"
  }
 },
 "snapshots": [
  {
   "date": "2026-06-01",
   "model_id": "claude-opus-4-8",
   "model_name": "Claude Opus 4.8",
   "event": "new_model",
   "pricing": {
    "input_per_million": 5.0,
    "output_per_million": 25.0
   },
   "context_max_tokens": 1000000,
   "note": "Claude Opus 4.8 launched May 28, 2026. $5/$25 standard; $10/$50 fast mode. SWE-Bench Pro 69.2%. 1M context window confirmed on platform.claude.com. Source: anthropic.com/news"
  },
  {
   "date": "2026-06-01",
   "model_id": "gpt-5-5",
   "model_name": "GPT-5.5",
   "event": "new_model",
   "pricing": {
    "input_per_million": 5.0,
    "output_per_million": 30.0
   },
   "context_max_tokens": 1048576,
   "note": "GPT-5.5 launched April 24, 2026. $5/$30 standard; $2.50/$15 batch. Source: openai.com/pricing"
  },
  {
   "date": "2026-06-01",
   "model_id": "gpt-5",
   "model_name": "GPT-5",
   "event": "new_model",
   "pricing": {
    "input_per_million": 1.25,
    "output_per_million": 10.0
   },
   "context_max_tokens": 400000,
   "note": "GPT-5 launched August 7, 2025. $1.25/$10. Source: openai.com/pricing"
  },
  {
   "date": "2026-06-01",
   "model_id": "gpt-5-mini",
   "model_name": "GPT-5 Mini",
   "event": "new_model",
   "pricing": {
    "input_per_million": 0.25,
    "output_per_million": 2.0
   },
   "note": "GPT-5 Mini — $0.25/$2.00. Cached input $0.025. Source: openai.com/pricing"
  },
  {
   "date": "2026-06-01",
   "model_id": "gemini-3-5-flash",
   "model_name": "Gemini 3.5 Flash",
   "event": "new_model",
   "pricing": {
    "input_per_million": 1.5,
    "output_per_million": 9.0
   },
   "context_max_tokens": 1048576,
   "note": "Gemini 3.5 Flash GA since May 19, 2026 (Google I/O). $1.50/$9.00. Source: ai.google.dev/pricing"
  },
  {
   "date": "2026-06-01",
   "model_id": "grok-4-3",
   "model_name": "Grok 4.3",
   "event": "new_model",
   "pricing": {
    "input_per_million": 1.25,
    "output_per_million": 2.5
   },
   "context_max_tokens": 1000000,
   "note": "Grok 4.3 — $1.25/$2.50; cached $0.20. Source: x.ai/api"
  },
  {
   "date": "2026-06-01",
   "model_id": "deepseek-v4-pro",
   "model_name": "DeepSeek V4-Pro",
   "event": "new_model",
   "pricing": {
    "input_per_million": 0.435,
    "output_per_million": 0.87
   },
   "context_max_tokens": 1000000,
   "note": "DeepSeek V4-Pro launched April 24, 2026. MIT license. Source: api-docs.deepseek.com/quick_start/pricing"
  },
  {
   "date": "2026-06-01",
   "model_id": "deepseek-v4-flash",
   "model_name": "DeepSeek V4-Flash",
   "event": "new_model",
   "pricing": {
    "input_per_million": 0.14,
    "output_per_million": 0.28
   },
   "context_max_tokens": 1000000,
   "note": "DeepSeek V4-Flash launched April 24, 2026. MIT license. Cheapest commercial API in this set. Source: api-docs.deepseek.com"
  },
  {
   "date": "2026-06-01",
   "model_id": "kimi-k2-6",
   "model_name": "Kimi K2.6",
   "event": "new_model",
   "pricing": {
    "input_per_million": 0.95,
    "output_per_million": 4.0
   },
   "context_max_tokens": 262144,
   "note": "Kimi K2.6 released April 20, 2026. Modified MIT. Source: platform.moonshot.ai/docs/pricing"
  },
  {
   "date": "2026-06-01",
   "model_id": "mistral-large-3",
   "model_name": "Mistral Large 3",
   "event": "new_model",
   "pricing": {
    "input_per_million": 0.5,
    "output_per_million": 1.5
   },
   "context_max_tokens": 256000,
   "note": "Mistral Large 3 released December 2, 2025. Apache 2.0. API id: mistral-large-2512. Source: mistral.ai/technology/models"
  },
  {
   "date": "2026-06-01",
   "model_id": "llama-4-maverick",
   "model_name": "Llama 4 Maverick",
   "event": "new_model",
   "pricing": null,
   "context_max_tokens": 1000000,
   "note": "Llama 4 Maverick released April 5, 2025. Community License. Self-hosted, no API fee. Source: ai.meta.com/llama"
  },
  {
   "date": "2026-06-01",
   "model_id": "llama-4-scout",
   "model_name": "Llama 4 Scout",
   "event": "new_model",
   "pricing": null,
   "context_max_tokens": 10000000,
   "note": "Llama 4 Scout released April 5, 2025. Community License. 10M token context. Self-hosted. Source: ai.meta.com/llama"
  },
  {
   "date": "2026-06-10",
   "model_id": "claude-fable-5",
   "model_name": "Claude Fable 5",
   "event": "new_model",
   "pricing": {
    "input_per_million": 10.0,
    "output_per_million": 50.0
   },
   "context_max_tokens": 1000000,
   "note": "Released June 9, 2026. Mythos-class, generally available with safety classifiers (cyber/bio/distillation fall back to Opus 4.8). Source: anthropic.com/news/claude-fable-5-mythos-5"
  },
  {
   "date": "2026-06-10",
   "model_id": "gpt-5-4",
   "model_name": "GPT-5.4",
   "event": "new_model",
   "pricing": {
    "input_per_million": 2.5,
    "output_per_million": 15.0
   },
   "context_max_tokens": 1000000,
   "note": "Re-added after verification. Released March 5, 2026; wrongly removed June 1 as 'unverified'. Source: openai.com/api/pricing"
  }
 ]
}