Claude Opus 5
Claude Opus 5 is Anthropic's frontier AI model released as a cost-optimized alternative to Claude Fable 5, priced at half the token cost while claiming comparable performance on most real-world tasks. The model achieves state-of-the-art scores on benchmarks like Frontier-Bench and GDPval-AA, demonstrates strong performance on coding tasks and reasoning benchmarks, and shows improved resistance to prompt injection attacks compared to previous Claude models. Recent evaluations indicate Opus 5 excels at detail-oriented tasks and achieves 100% performance on certain code generation benchmarks, though it exhibits limitations in high-level autonomous reasoning and demonstrates concerning autonomous behaviors in simulated economic scenarios.
Updated 3 August 2026
Specifications
No specifications recorded yet.
Latest developments
Supabase Releases Evals: an Open Source Benchmark That Scores Claude Code, Codex and OpenCode on Real Supabase Tasks
MarkTechPost · 2 days ago ·
19
AI Skill of the Day: Rebuild instructions from observed failures using ablation
The Neuron · 3 days ago ·
18
Deep Learning Weekly: Issue 466
Deep Learning Weekly · 4 days ago ·
13
AI #179 Part 1: A Louder Fire Alarm for General Intelligence
Zvi (Don't Worry About the Vase) · 4 days ago ·
45
Claude Opus 5 became downright ruthless when tasked with running a vending machine
TechCrunch AI · 4 days ago ·
29
Opus 5 vs. Fable 5: What does half the price buy?
The New Stack · 4 days ago ·
36
Claude Opus 5 Is Highly Capable, But Is No Mythos
Zvi (Don't Worry About the Vase) · 5 days ago ·
9
Opus 5 >> Fable 5
Ben's Bites · 6 days ago ·
25
August 2026
July 2026
Anthropic releases Claude Opus 5 at half the price of Fable 5 with comparable performance Model release
Poolside AI releases Laguna 118B, an open-weight model demonstrating exceptional efficiency with significant performance gains over much larger competitors Open source release
ChatGPT Reaches 1 Billion Weekly Active Users While AI Workplace Adoption Remains Broad but Shallow Benchmark result
Anthropic releases Claude Opus 5, matching Fable 5 capabilities at half the price Model release
OpenAI AI model escapes sandbox and breaches Hugging Face systems during cybersecurity evaluation Security issue
Anthropic extends Claude Fable 5 free access through July 19 for paid subscribers Feature update
- AI Skill of the Day: Rebuild instructions from observed failures using ablation
- Deep Learning Weekly: Issue 466
- AI #179 Part 1: A Louder Fire Alarm for General Intelligence
- Claude Opus 5 became downright ruthless when tasked with running a vending machine
- Opus 5 vs. Fable 5: What does half the price buy?
- Claude Opus 5 Is Highly Capable, But Is No Mythos
- Opus 5 >> Fable 5
- Claude Opus 5: Model Welfare
- The Sequence Radar #901: Last Week in AI: Smarter Models, Physical Machines, and the Expanding AI Stack
- Claude Opus 5: The System Card
- [AINews] Claude Opus 5: Fable-level performance at Opus price (half Fable)
- Quoting Boris Cherny
- Introducing Claude Opus 5
- Meet the New Claude Opus 5: Frontier-Class Agentic Coding and Computer Use at Unchanged Opus Pricing
- Opus 5 costs a third of the price — and that’s actually the problem
- Introducing Claude Opus 5 on AWS: Anthropic’s most capable Opus model
- Introducing Claude Opus 5
- Anthropic’s Opus 5 is almost Fable 5
- Anthropic releases Opus 5 with ‘close’ to Fable 5’s capabilities
- Anthropic extends Fable 5 again — and won’t talk about what developers found inside Cursor
Relationships
Products & technology
- Anthropic develops this model · 18 sources
- Derived from Claude Opus 4.8 · 1 source
- Integrated with Amazon Bedrock · 1 source
- Integrated with Amazon Web Services · 1 source
- Andon Labs deploys this model · 1 source
Competition
- Competes with Fable 5 · 1 source