Loading timeline…
20262020s
Claude Opus 5
Anthropic released Claude Opus 5 on July 24, 2026, delivering near-Fable performance at half the price with a 1M-token context and adaptive thinking by default.
Why It Mattered
Opus 5 brought Mythos-adjacent capability to the mass market, landing within 0.5% of Fable 5's peak on key coding benchmarks at half the cost per task, with a 1-million-token context window, up to 128K output tokens, and a five-level effort setting for controlling reasoning depth. It crystallized the 2026 dynamic in which frontier capability filtered down to affordable tiers within weeks, accelerating enterprise adoption of long-horizon agentic workloads.
Who Built It
Anthropic
Applications
- Agentic Coding
- Enterprise AI
- Long-context Analysis