Claude

Claude Fable 5 is Anthropic's Mythos-class model released on June 9, 2026, focused on creative writing, worldbuilding, and narrative depth. It was suspended from distribution on June 12, 2026, under US export controls, making it a limited-availability release.

Claude Opus 5.5 is Anthropic's September 22, 2026 update to Opus 5, priced at $4 per million input tokens and $20 per million output (down from $5/$25), with cache reads cut from $0.50 to $0.20 per million and cache writes from $6.25 to $5. A faster mode in Claude Code and the Claude Platform runs up to 2.5x quicker at $8/$40 per million tokens. Anthropic's own benchmarks put it ahead of the larger Claude Fable 5.1 on agentic coding (66.4% vs 55.8% on Terminal-Bench 4.0), computer use (81.8% vs 80.7% on OSWorld 2.0), and knowledge work (1846 vs 1735 Elo on GDPval-AA v2.1), while generating...

Claude Opus 5 is Anthropic's flagship model, released 24 July 2026 with a 1M-token context window and five selectable effort levels (low, medium, high, xhigh, max). Effort is the main control: output token spend runs roughly 8x from low to max, and Artificial Analysis measures a 407-Elo spread in task quality across that range, so the same model behaves like several different price and capability tiers. API pricing is $5 per million input tokens and $25 per million output, with cache writes at $6.25 and cache hits at $0.50. It leads the Intelligence Index at 60.7 and tops the Coding Agent...