{
 "product": "YFarmX Model Identity",
 "method": "tokenizer fingerprinting v1-50",
 "updated": "2026-08-22",
 "record_url": "https://yfarmx.com/ai/models/stepfun/step-3.7-flash/",
 "citation": "YFarmX Model Identity: StepFun: Step 3.7 Flash (stepfun/step-3.7-flash) evidence record. Measured 2026-08-21. https://yfarmx.com/ai/models/stepfun/step-3.7-flash/",
 "record": {
  "id": "stepfun/step-3.7-flash",
  "slug": "stepfun/step-3.7-flash",
  "name": "StepFun: Step 3.7 Flash",
  "lab": "StepFun",
  "alias": false,
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  "description": "Step 3.7 Flash is StepFun's latest high-efficiency multimodal Mixture-of-Experts model. It pairs a 196B-parameter language backbone with a vision encoder for native image and video understanding, activating roughly 11B parameters...",
  "declared": {
   "tokenizer": "Other",
   "modality": "text+image+video->text",
   "input": [
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   "max_output": 256000,
   "pricing": {
    "prompt": "0.0000002",
    "completion": "0.00000115"
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   "params": [
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    "seed",
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    "tool_choice",
    "tools",
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   "defaults": {
    "temperature": null,
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    "presence_penalty": null,
    "repetition_penalty": null
   },
   "reasoning": {
    "mandatory": true,
    "supported_efforts": [
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   },
   "hugging_face": "stepfun-ai/Step-3.7-Flash"
  },
  "measurement": {
   "status": "measured",
   "at": "2026-08-21",
   "run": "catalogue-sweep",
   "overhead": 12,
   "providers": [
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   ],
   "clean_rows": 50,
   "corrupt_rows": 0,
   "signature": "tk_73c4f0dc",
   "counts": {
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    "zh-common": 9,
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    "zh-rare": 18,
    "ja-kana": 9,
    "ja-kanji": 11,
    "ko": 13,
    "ru": 13,
    "ar": 10,
    "he": 14,
    "hi": 18,
    "th": 11,
    "el": 16,
    "emoji-basic": 10,
    "emoji-skin": 14,
    "emoji-zwj-family": 11,
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    "emoji-flags": 16,
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    "math": 22,
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    "combining": 10,
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    "py-code": 25,
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    "json": 20,
    "html": 16,
    "regex": 47,
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    "rare-word-x5": 26,
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    "base64": 34,
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    "uuid": 27
   },
   "corrupt": {},
   "observations": [
    {
     "at": "2026-08-21",
     "run": "catalogue-sweep",
     "clean": 50
    }
   ]
  },
  "note": {
   "date": "2026-08-21",
   "text": "As with Step 3.5 Flash: StepFun's own Step-3 repository ships a tokenizer behaviourally identical to DeepSeek-V3's over all 50 strings, and this endpoint counts the same way. Its place in the DeepSeek signature group is genuine lineage reuse by StepFun.",
   "sources": [
    {
     "label": "StepFun step3 repository (config.json)",
     "url": "https://huggingface.co/stepfun-ai/step3/blob/main/config.json"
    }
   ]
  },
  "api_signature": "api_941e54b9",
  "api_matches": [],
  "identity": {
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   "family": "DeepSeek",
   "confidence": "high",
   "confidence_reason": "an exact fingerprint shared with 9 models that declare the same family, without a second signal of a different kind yet",
   "basis": [
    "exact tokenizer signature shared with 9 models"
   ],
   "contradiction": null,
   "declared_vs_measured": "resolved"
  },
  "comparator": "deepseek/deepseek-v4-pro-0813",
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   },
   {
    "id": "deepseek/deepseek-v4-flash",
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   },
   {
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   },
   {
    "id": "deepseek/deepseek-v3.2",
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   },
   {
    "id": "deepseek/deepseek-v3.2-exp",
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    "total": 50
   }
  ]
 }
}