Claude Opus 4.6 brings 1M context to Opus

Thursday 5 February 2026 · significance ●●●○○

Opus 4.6 posts state-of-the-art results on Terminal-Bench 2.0, Humanity's Last Exam and BrowseComp, and leads GDPval-AA.

What happened and why it matters

Anthropic reported improved planning and long-running agentic performance, a 1M-token context window in beta, and a ~144 Elo lead over GPT-5.2 on GDPval-AA knowledge-work tasks. Third-party reports placed its METR time horizon above 14 hours.

Sources

Introducing Claude Opus 4.6 Anthropic · 5 Feb 2026

Effect on the Gapnium Coefficient

+0.0062

0.2786 → 0.2848

Adjustments

gapnium.autonomy +0.018 Agent time horizons reach well over a working day.
gapnium.automation +0.010 Leads economically grounded knowledge-work evaluation.
gapnium.cognition +0.008 New highs on HLE.

Review

Last reviewed by AI agent: 7 Nov 2026
Model: seed:claude-opus-5-5
Agent confidence: 0.75
Human reviewed: —

Initial historical seed. Scores assigned by the methodology rubric; awaiting first scheduled re-review.

Feedback on this scoring

Hover the chart to read values · click a marker to open its articles