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BenchLM

Legal Agent Benchmark all-pass rate — Anthropic harness (LAB all-pass (Anthropic harness))

We show this table for reference; we do not rank on it.

Data verified 34 confirmed releases in the last 30 daysFollow model changes

Strict task success requiring every expert-written legal-work rubric criterion to pass.

Benchmark score on LAB all-pass (Anthropic harness) — September 27, 2026

We compile the LAB all-pass (Anthropic harness) rows from provider self-reports. Claude Opus 5 leads the table at 23.58%. We do not use these results to rank models overall.

1 modelAgenticCurrentDisplay onlyUpdated September 27, 2026

Benchmark score table (1 model)

Score
1
Claude Opus 5Anthropic · Closed
23.58%

About LAB all-pass (Anthropic harness)

Year

2026

Tasks

1,235 legal-agent tasks

Format

All-criteria pass rate

Difficulty

Professional legal work

Section 8.13.3 reports five-run performance on 1,235 tasks using Anthropic's reduced-tool reimplementation, production safeguards, and fallback to Opus 4.8 on classifier refusal.

Freshness and provenance

Version

LAB all-pass (Anthropic harness) 2026

Refresh cadence

Quarterly

Staleness state

Current

Question availability

Public benchmark set

CurrentDisplay only

BenchLM uses freshness metadata to decide whether a benchmark should still be treated as a strong differentiator, a benchmark to watch, or a display-only reference. For the full scoring policy, see the BenchLM methodology page.

Questions

What does LAB all-pass (Anthropic harness) measure?

Strict task success requiring every expert-written legal-work rubric criterion to pass.

Which model scores highest on LAB all-pass (Anthropic harness)?

Claude Opus 5 by Anthropic currently leads with a score of 23.58% on LAB all-pass (Anthropic harness).

How many models are evaluated on LAB all-pass (Anthropic harness)?

1 AI models have been evaluated on LAB all-pass (Anthropic harness) on BenchLM.

Last updated: September 27, 2026 · BenchLM version LAB all-pass (Anthropic harness) 2026

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