The agentic leaderboard just flipped to anthropic, and it’s a price story. opus 5.5 scores 89.9% on…
the agentic leaderboard just flipped to anthropic, and it’s a price story. opus 5.5 scores 89.9% on swe-bench pro — the record, ahead of fable 5.1 on every coding line anthropic publishes — at $20/m output, about 40% cheaper to run than opus 5.
frontier coding is now a budget item, not a prestige one.
Context
Verified source: Anthropic's Claude Opus 5.5 page is dated Sep 22, 2026. It prices Opus 5.5 at $4 input and $20 output per million tokens, 20% less than Opus 5, and says it costs 40% less than Opus 5 on typical workloads. The platform docs list a 1M context window.
LLMBoard lists Opus 5.5 at 89.90% on SWE-Bench Pro, rank 1 of 61 participants, evaluated Oct 11, 2026.
The $20 per million output and the roughly 40% lower cost than Opus 5 match Anthropic's page. The 89.9% and the first place match a third-party board, evaluated Oct 11, not a figure from Anthropic's page excerpt read here. That it leads 'fable 5.1 on every coding line anthropic publishes' was not seen in the sources read, so unsupported here, not refuted. 'Frontier coding is now a budget item' is the author's opinion.
Related work
- Claude Opus page, Anthropic ↗Availability and pricing.
- Claude docs ↗Breaking changes from Opus 5.
- LLMBoard ↗Third-party scores, Oct 11.
Watch next
- Read the Anthropic page for the benchmark table behind the SWE-Bench Pro claim.
Sources
- Introducing Claude Opus 5.5, Anthropicanthropic.com
- Claude Opus 5.5 overview, Claude docsplatform.claude.com
- Claude Opus 5.5 benchmarks, pricing and specs, LLMBoardllmboard.ai
Provenance
The note above is reproduced unedited from the original post, first published on Threads on 1 October 2026 at 06:17 IST. Sources are the papers and datasets the note draws on.
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