Who ranks #1 on the Legal Agent Benchmark (Held-out) leaderboard?
As of September 1, 2026, Claude Fable 5.1 by Anthropic ranks #1 on Legal Agent Benchmark (Held-out) at 16.7%. API pricing is $10.00/M input and $50.00/M output.
As of September 1, 2026, Claude Fable 5.1 is #1 for Legal Agent Benchmark (Held-out) at 16.7%. Ranked by the Legal Agent Benchmark (Held-out) score 2 models in this index have a published Legal Agent Benchmark (Held-out) score. Legal Agent Benchmark (Held-out) leaderboard with live API prices. Legal Agent Benchmark held-out — Artificial Analysis's private Harvey LAB split.
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As of September 1, 2026, Claude Fable 5.1 by Anthropic is #1 for Legal Agent Benchmark (Held-out) at 16.7%. Ranked by the Legal Agent Benchmark (Held-out) score This board also tracks Legal Agent Benchmark (Held-out). Next on the same board: Claude Mythos 5.1. This legal agent benchmark (held-out) leaderboard ranks models by Legal Agent Benchmark (Held-out). Scores come from public evals. Prices are the live API rates in the table above.
Sources: OpenAI API pricing (https://developers.openai.com/api/docs/pricing); Anthropic Claude API pricing (https://platform.claude.com/docs/en/about-claude/pricing); Gemini API pricing (https://ai.google.dev/gemini-api/docs/pricing)
| Rank | Model | Legal Agent Benchmark (Held-out) | Input /M | Output /M |
|---|---|---|---|---|
| 1 | Claude Fable 5.1 | 16.7% | $10.00 | $50.00 |
| 2 | Claude Mythos 5.1 | 16.7% | $10.00 | $50.00 |
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As of September 1, 2026, Claude Fable 5.1 by Anthropic ranks #1 on Legal Agent Benchmark (Held-out) at 16.7%. API pricing is $10.00/M input and $50.00/M output.
The current Legal Agent Benchmark (Held-out) ranking as of September 1, 2026 is 1. Claude Fable 5.1 at 16.7%; 2. Claude Mythos 5.1 at 16.7%.
Claude Fable 5.1 currently leads Legal Agent Benchmark (Held-out) and is also the cheapest scored model on this page, at $10.00/M input and $50.00/M output ($60.00 blended).
Not automatically. Claude Fable 5.1 leads Legal Agent Benchmark (Held-out), but a cheaper scored model can be the better production choice if the quality gap is small. Use the table to weigh Legal Agent Benchmark (Held-out) against input/output price, context window, and related evals.
Scores and API prices on this page are refreshed from published evals and provider rates. The snapshot is labeled September 1, 2026. Treat it as a current index, not a one-off blog post.
Legal Agent Benchmark held-out — Artificial Analysis's private Harvey LAB split. This page ranks models that have published a Legal Agent Benchmark (Held-out) score, with live API token prices on the same row.
This page is the Legal Agent Benchmark (Held-out) leaderboard. Models are sorted by Legal Agent Benchmark (Held-out), with input and output token prices on the same row so you can weigh score against cost. Official boards often omit price; that comparison is the point of this index.
Official eval pages own the methodology. This page keeps the published Legal Agent Benchmark (Held-out) score next to live API $/M so you can pick a production SKU, not only a trophy number.