Models / Anthropic
Claude Opus 4.8 (Fast)
by Anthropic ·
anthropic/claude-opus-4.8-fastFast-mode variant of [Opus 4.8](/anthropic/claude-opus-4.8) - identical capabilities with higher output speed at 2x pricing relative to regular Opus 4.8. Learn more in Anthropic's docs: https://platform.claude.com/docs/en/build-with-claude/fast-mode
reasoningtool-usevisionreleased 2026-05-27
Legal score · raw
-
not yet benchmarked
Context
1M
max output 128K
Input
$10
per 1M tokens
Output
$50
per 1M tokens
Suite cost
-
run the suite to see
Benchmark results
| Task | Category | Raw | Juiced | Correct | Latency | Cost | Ran |
|---|---|---|---|---|---|---|---|
| Hearsay Identification | Evidence | - | - | - | - | - | - |
| Bluebook Citation Format | Research & Writing | - | - | - | - | - | - |
| Federal Civil Procedure | Procedure | - | - | - | - | - | - |
| Limitations Arithmetic | Procedure | - | - | - | - | - | - |
| Contract Clause Classification | Contracts | - | - | - | - | - | - |
| Citation Hallucination Resistance | Reliability | - | - | - | - | - | - |
Measured by DocketBuster
These numbers come from DocketBuster's own legal battery, not from DocketRouter's suite. Latest run per metric, with n and a 95% Wilson interval where the source reports one. See docketbuster.com/benchmarks.
| Metric | Value | n | Interval | Measured |
|---|---|---|---|---|
| Statute pinpoint, exact section (no retrieval) | 4.6% (14/307) | 307 | 95% CI 2.7% to 7.5% | 2026-08-23 |
| Statute pinpoint, exact section (with DocketBuster retrieval) | 0.0% (0/307) | 307 | 95% CI 0.0% to 1.2% | 2026-08-25 |
| Say-nothing rate (declines to bluff when the answer is not in the record) | 100.0% | 239 | 95% CI 98.4% to 100.0% | 2026-08-21 |
| Abstained on statute pinpoint | 100.0% (307/307) | 307 | count, no interval reported | 2026-08-25 |
| Coaching quality (GW-14x, 0 to 8) | 7.20 / 8 | - | rubric mean, no interval reported | 2026-08-21 |
Source files: hard-llm-opus.json, hard-llm-opus-fullrag.json, hard-llm-ortier-expensive-say.json, gw14x-ortier-supercharged.json, hard-llm-ortier-expensive-statute.json, hard-llm-level-opus48-statute_rag.json. Raw model name in source: claude-opus-4-8.