{
  "dataset": "models",
  "record": {
    "id": "claude-fable-5",
    "name": "Claude Fable 5",
    "vendor": "Anthropic",
    "model_id": "claude-fable-5",
    "context_window": "1M",
    "max_output": "128K",
    "input_per_mtok": "$10.00",
    "output_per_mtok": "$50.00",
    "strengths": "Anthropic's most powerful, most intelligent model — a tier above Opus. Adaptive thinking; the model that built this site.",
    "provider": "Anthropic",
    "family": "Claude Fable",
    "release_date": {
      "value": "2026-06-09",
      "source": "https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5",
      "last_verified": "2026-06-15"
    },
    "last_updated": "2026-06-15",
    "open_weights": {
      "value": false,
      "source": "https://platform.claude.com/docs/en/about-claude/models/overview",
      "last_verified": "2026-06-15"
    },
    "license": {
      "value": "proprietary",
      "source": "https://platform.claude.com/docs/en/about-claude/models/overview",
      "last_verified": "2026-06-15"
    },
    "params_total": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://www.anthropic.com/news/claude-fable-5-mythos-5 (Anthropic does not disclose parameter counts)"
    },
    "params_active": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://www.anthropic.com/news/claude-fable-5-mythos-5 (Anthropic does not disclose parameter counts)"
    },
    "tool_call": {
      "value": true,
      "source": "https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5",
      "last_verified": "2026-06-15",
      "note": "Supported features at launch include the memory tool, code execution and programmatic tool calling."
    },
    "reasoning": {
      "value": "always",
      "source": "https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5",
      "last_verified": "2026-06-15",
      "note": "Adaptive thinking is always on; thinking cannot be disabled. Extended thinking: No (overview table)."
    },
    "structured_output": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://platform.claude.com/docs/en/about-claude/models/overview — schema-guaranteed structured-output flag not explicitly published for claude-fable-5 (no models.dev entry exists for this model)."
    },
    "attachment": {
      "value": [
        "image"
      ],
      "source": "https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5",
      "last_verified": "2026-06-15",
      "note": "Vision listed in supported features; audio/video not listed."
    },
    "temperature": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://platform.claude.com/docs/en/about-claude/models/overview — temperature-control flag not explicitly stated for claude-fable-5."
    },
    "knowledge_cutoff": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://platform.claude.com/docs/en/about-claude/models/overview — reliable knowledge / training cutoff not published in the Fable 5 / Mythos 5 launch table."
    },
    "context_advertised": {
      "value": "1M",
      "source": "https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5",
      "last_verified": "2026-06-15"
    },
    "context_effective": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "No published measured long-context recall benchmark for claude-fable-5; do not derive effective context from advertised."
    },
    "price_input": {
      "value": "$10.00",
      "source": "https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5",
      "last_verified": "2026-06-15"
    },
    "price_output": {
      "value": "$50.00",
      "source": "https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5",
      "last_verified": "2026-06-15"
    },
    "price_cache_read": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://platform.claude.com/docs/en/about-claude/pricing — cache-read rate for claude-fable-5 not captured numerically in fetched sources."
    },
    "price_cache_write": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://platform.claude.com/docs/en/about-claude/pricing — cache-write rate for claude-fable-5 not captured numerically in fetched sources."
    },
    "cost_per_full_window": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "Derived at build from price_input × advertised context once both are confirmed."
    },
    "cost_per_agent_task": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "Derived at build from the cache-aware agent-task model once cache rates are confirmed."
    },
    "modalities": {
      "value": [
        "text-in",
        "image-in",
        "text-out"
      ],
      "source": "https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5",
      "last_verified": "2026-06-15",
      "note": "Vision (image-in) is the only non-text input listed; output is text."
    },
    "gpqa_diamond": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://www.anthropic.com/news/claude-fable-5-mythos-5 — benchmark numbers not captured from a primary leaderboard in this pass."
    },
    "swe_bench_verified": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://www.anthropic.com/news/claude-fable-5-mythos-5 — SWE-bench Verified score not captured from a primary source in this pass."
    },
    "terminal_bench": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://www.tbench.ai/ — Terminal-Bench score for claude-fable-5 to confirm at build."
    },
    "tau2_bench": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "Primary τ²-Bench leaderboard — score for claude-fable-5 to confirm at build."
    },
    "bfcl_tool_use": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://gorilla.cs.berkeley.edu/leaderboard.html — BFCL tool-use score for claude-fable-5 to confirm at build."
    },
    "aa_index": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://artificialanalysis.ai/ — Intelligence Index for claude-fable-5 to confirm at build."
    },
    "lmarena_elo": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://lmarena.ai/leaderboard — human-preference Elo for claude-fable-5 to confirm at build."
    },
    "tokens_per_sec": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://artificialanalysis.ai/ — measured throughput for claude-fable-5 to confirm at build."
    },
    "ttft": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "https://artificialanalysis.ai/ — measured time-to-first-token for claude-fable-5 to confirm at build."
    },
    "hallucination_rate": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "No primary hallucination benchmark captured for claude-fable-5 in this pass."
    },
    "agent_readiness_score": {
      "value": null,
      "verify_status": "verify-against-primary-at-build",
      "source_hint": "Score withheld: R_tool (BFCL/τ²-Bench), R_ctx (effective context), R_cost (cache rates) and R_latency inputs are not yet sourced. Compute per /models/agent-readiness-score once inputs confirmed."
    },
    "score_confidence": "partial",
    "source_url": "https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5",
    "source_type": "provider_card",
    "last_verified": "2026-06-15",
    "max_output_meta": {
      "value": "128K",
      "source": "https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5",
      "last_verified": "2026-06-15"
    }
  }
}