{
  "api_version": "1",
  "updated": "2026-10-26",
  "latest_event": "2026-10-24",
  "rights": "© Frontier Log, all rights reserved.",
  "model": {
    "slug": "claude-mythos-5-1",
    "name": "Claude Mythos 5.1",
    "lab": "anthropic",
    "date": "2026-09-01",
    "source": "https://www.anthropic.com/claude-fable-and-mythos-5-1",
    "source_title": "Introducing Claude Fable 5.1 and Claude Mythos 5.1",
    "flagship": false,
    "event": "https://frontierlog.ai/event/2026-09-01-claude-fable-5-1-mythos-5-1",
    "releases": [],
    "variant_of": null,
    "made_by": "Anthropic",
    "url": "https://frontierlog.ai/model/claude-mythos-5-1",
    "results": [
      {
        "id": "claude-mythos-5-1:terminal-bench-4-0:default:1",
        "model": "claude-mythos-5-1",
        "model_name": "Claude Mythos 5.1",
        "model_date": "2026-09-01",
        "event": "https://frontierlog.ai/event/2026-09-01-claude-fable-5-1-mythos-5-1",
        "benchmark": "terminal-bench-4-0",
        "benchmark_name": "Terminal-Bench 4.0",
        "setting": "default",
        "setting_name": "",
        "score": 60.9,
        "unit": "%",
        "printed": "60.9%",
        "reported_by": "anthropic",
        "run_by": null,
        "label": "Mythos 5.1",
        "source": "https://www.anthropic.com/claude-fable-and-mythos-5-1",
        "source_title": "Introducing Claude Fable 5.1 and Claude Mythos 5.1",
        "source_date": "2026-09-01",
        "where": "benchmark table (HTML), row 'Agentic coding, Terminal-Bench 4.0', column 'Fable 5.1', the second value, labelled '(Mythos 5.1)'",
        "own": true,
        "primary": true,
        "parallel": false,
        "notes": "",
        "caveat": "",
        "human_verified": true,
        "human_verified_on": "2026-10-19",
        "check": "human",
        "corroborated": true,
        "corroborated_on": "2026-10-19",
        "corroborated_by": [
          {
            "url": "https://www.anthropic.com/claude-fable-5-1-mythos-5-1-system-card",
            "name": "Claude Fable 5.1 and Mythos 5.1 card",
            "title": "Claude Fable 5.1 and Claude Mythos 5.1 System Card",
            "lab": "anthropic",
            "date": "2026-09-01",
            "printed": "60.9%",
            "where": "section 8.5 sentence: 'Claude Mythos 5.1 scored 60.9% on Terminal-Bench 4.0' (Table 8.1.A prints it as '(61%)' under Fable 5.1/Mythos 5.1)"
          }
        ],
        "source_capture": "https://frontierlog.ai/captures/f381a9ad69b68272.png"
      }
    ]
  }
}