Claude Opus 5
A thoughtful and proactive model that comes close to the frontier intelligence of Claude Fable 5 at half the price.
A specific Anthropic Claude Opus 5 model release, referenced in the supplied 2026 evidence context as an agentic, multimodal-capable model used through Claude Code and Codex.
Pricing
All prices are USD per million tokens (MTok). Official table lists 5m cache writes at $6.25/MTok, 1h cache writes at $10/MTok, and cache hits and refreshes at $0.50/MTok.
Anthropic's official pricing documentation explicitly lists Claude Opus 5 at $5 per million input tokens and $25 per million output tokens. It also lists cache hits and refreshes at $0.50 per million tokens, with cache writes at $6.25 per million tokens for 5-minute writes and $10 per million tokens for 1-hour writes.
Model Intelligence
Recent stories
Researchers say a three-person team used Claude and other frontier models to exploit a Discourse vulnerability affecting OpenAI. Posts report the campaign took two days and earned a $6,500 bug bounty.
Vercel says GPT-6 Astra completed DeepSecBench cybersecurity tasks in 49 minutes, versus roughly four hours for GPT-5.6 Sol. It reported a higher score at nearly the same cost per task.
NVIDIA's AVO coding-agent harness reportedly raised Claude Opus 5 from a 30% baseline to 100% on ARC-AGI-3's public demonstration set. ARC-AGI's creator says the result is not a full benchmark score.
ARC Prize verified Gemini 3.7 Flash at 84.6% on ARC-AGI-2, at a reported $0.25 per task. Artificial Analysis’ AnalystAgent benchmark placed it at 60%, ahead of Claude Opus 5 and GPT-5.5.
Claude Code users reported Fable 5 and Opus 5 sessions exhausting five-hour usage windows in about 6–10 minutes after automated tool calls. The reports tie the failures to agent loops and rate-limit economics, including one Reddit claim of 10.26M tokens, 15 calls, and no edits.
Agent Arena says Claude Opus 5 Max placed second and Opus 5 High placed third across more than 7,000 real agentic sessions. Practitioner reports remain mixed across harnesses and prompting styles.
Claude Opus 5 combined benchmark wins with coding-agent reliability complaints. It led ProgramBench and Arena frontend rankings, while users reported overbuilding, missed intent, and switches back to Fable.
New benchmark posts put Claude Opus 5 first on LLM Debate, a short-story test, Extended NYT Connections, and DeepSWE. Developers also reported over-editing and long-session failures, making private evals a recurring caveat.
Anthropic released Claude Opus 5 with Fast Mode on paid plans and the API at the Opus 4.8 price. Benchmarks from ARC Prize, Artificial Analysis, Vals AI, and tool vendors put it near or ahead of Fable 5 on several agent and coding tests.