Claude Opus 4
Claude Opus 4 is a model from Anthropic, released on May 22, 2025 alongside Claude Sonnet 4, with both near-instant and extended-thinking modes.
Retired. Anthropic retired Claude Opus 4 from the Claude API on June 15, 2026 and recommends Claude Opus 4.8 in its place. Its price list shows it still offered on Google Cloud.
Released
May 22, 2025
Type
reasoning
License
proprietary
Context
—
Benchmarks
| SWE-bench VerifiedAnthropic’s figure: all 500 tasks, without extended thinking. | 72.5% |
Scores are the developer's own published figures for this model, under the test conditions noted. Benchmarks with no primary source are not listed.
Capabilities
Sources
Every figure on this page was checked against these pages on . A figure we could not source is left out.
- Anthropic news: Claude 4 (opens in a new tab)
- Claude docs: Model deprecations (opens in a new tab)
- Claude docs: Pricing (opens in a new tab)
Spotted something out of date? Tell us.
Links
In the news: Claude Opus 4 and Anthropic
MarkTechPost
Nace AI Releases Drex for Search for AI Agents: 92.05% on BrowseComp-Plus With 12.6 Search Calls
Nace AI has released Drex for Search, a retrieval layer that integrates its Drex decision models into document search to assist AI agents in finding evidence. This system is designed to be called by coding agents such as Claude Code, Codex, Cursor, and OpenCode via CLI, SDKs, MCP, or REST. In Nace's own evaluations, Drex for Search achieved a score of 92.05% on the BrowseComp-Plus benchmark when paired with GPT-5, utilizing an average of 12.6 search calls per question. The system is described as a hosted search solution capable of searching over one million files and can be paired with answering models like GPT-5, Gemini 3.5 Flash, or Qwen 27B. Drex for Search can be deployed on Nace's managed cloud, dedicated clouds, or users' own AWS or Azure accounts, as well as on-premises and in air-gapped environments. Nace reports that the system ranks first or second on three out of four public leaderboards, including achieving 77.5% R@1 on VisDocAgentBench, which is 10 points higher than Claude Opus 5. Nace AI frames search as a series of decisions, and Drex for Search applies its models to these decisions by scoring options with a calibrated probability in a single forward pass, making it cost-effective for each agent step. The system targets limitations in classic RAG pipelines, such as answers being located in tables, requiring cross-file hops, or being within scanned PDFs. Within an agent, Drex for Search operates in three steps: Classify, where it determines if a question requires a quick lookup or an agent route; Squeeze, where it narrows down the search space by navigating through folders, files, sections, and tables; and Answer, where only relevant pages and tables are sent to the LLM, with citations to the file and page number.
The A.V. Club
Anthropic sued for allegedly stealing from The King
Anthropic is being sued by the rights holders of Elvis Presley's music catalog, Authentic Brands Group, for allegedly using copyrighted songs to train its Claude large language model (LLM). The lawsuit claims Claude scooped up approximately 274 copyrighted Presley songs to generate AI-generated content. According to the filing, Claude has created infringing output of copyrighted material from virtually every song available on the internet, including the Elvis Presley works. Even after Anthropic implemented 'guardrails,' the lawsuit alleges that Claude continues to infringe. When recently asked to recreate specific songs for a modern audience, Claude reportedly admitted that its renders were very close to the originals, featuring the same structure, reused hooks with slight rewording, and full sets of verses, choruses, and bridges. Authentic Brands Group is seeking $150,000 per infringed Elvis song, totaling around $41.5 million. This lawsuit highlights the growing legal challenges surrounding AI's habit of scraping copyrighted material for training purposes.
MarkTechPost
Anthropic Launches OSS Scanner, a Free AI Vulnerability Scanner
Anthropic has launched OSS Scanner, a free, opt-in vulnerability scanner designed for critical open-source projects. This tool utilizes Anthropic's most powerful AI models, including Claude Mythos, to analyze enrolled codebases. Reports generated by OSS Scanner are sent directly to project maintainers without an initial human review. This approach aims to accelerate the discovery of vulnerabilities, though it shifts the triage work to the project teams. As of October 19, Anthropic reported 77 critical and 803 high model-rated findings. The program has accepted 114 projects out of approximately 650 applications. OSS Scanner runs on Anthropic's infrastructure at no cost to users. Maintainers provide a Dockerfile, and audits are conducted within an isolated virtual machine that has no internet access. Of the 97 audited critical and high findings, 85% met Anthropic's disclosure criteria. The scanner demonstrated a low false positive rate, with only 1 of 97 audited findings being a false positive. For example, wolfSSL stated that 72 out of 74 reports were valid. The design of OSS Scanner draws inspiration from Google's OSS-Fuzz, substituting fuzzers with language models to address review bottlenecks. Over a six-month period, Anthropic's models identified over 29,000 candidate vulnerabilities, with human reviewers triaging about 6,000. The OSS Scanner program is an evolution of an ad hoc request system where nearly 5,000 additional reports were sent directly to maintainers who had requested all findings, regardless of validation. To enroll, core maintainers submit a pull request to anthropics/oss-scanner, adding a project configuration file. This file requires repository details, a primary contact, and a Dockerfile path, with optional fields for threat models and encrypted reports.
MarkTechPost
Meet Anthropic’s sandbox-runtime: OS-Level Sandboxing for AI Agents, No Containers
Anthropic has open-sourced its sandbox-runtime (srt), an OS-level tool that provides sandboxing for AI agents. The runtime limits file access and network connectivity for processes without requiring containers. It is compatible with custom agents, local MCP servers, and plain command-line programs. The npm package, @anthropic-ai/sandbox-runtime v0.0.81, is approximately 11.4 MB unpacked and released under the Apache-2.0 license. It requires Node.js 22.12+ and runs on macOS and Linux development machines or CI systems. Windows support is currently in an alpha stage. On macOS, srt utilizes Seatbelt for isolation, while Linux requires bubblewrap, socat, and ripgrep. Anthropic reports that internal usage of srt reduced permission prompts for Claude Code by 84%, enforcing file and network limits across the entire process tree. The sandbox-runtime functions as a command-line interface (CLI) and a TypeScript library. Users can install it via npm and prefix commands with 'srt' to apply restrictions. The tool leverages each operating system's native isolation primitives to enforce its security policies on the entire process tree.
MarkTechPost
You.com Launches Inference Router: 12 Open-Weight Models With 99.9% Uptime SLA
You.com has launched Inference Router, a managed API designed for deploying open-weight AI models in production environments. This service is compatible with OpenAI and Anthropic APIs, allowing developers to integrate existing SDK code by updating the base URL and API key. The Inference Router provides access to 12 live open-weight models, ranging from GPT-OSS 120B with a 125K context window to Kimi K3 and Qwen3.8 Max, which support up to a 1 million context window. Kimi K3 is a 2.8 trillion parameter model, and Qwen3.8 Max is a 2.4 trillion parameter Mixture-of-Experts (MoE) model. The service includes a 99.9% minimum uptime Service Level Agreement (SLA) and implements zero data retention (ZDR). It also features 100% US hosting and server-side web search capabilities, operating on a pay-as-you-go model without any platform fees. Requests are initially routed to You.com's own inference capacity, Inference Direct. If this capacity is unavailable or full, requests automatically fail over to vetted, 100% US-hosted partners including Parasail, Wafer, Alibaba Cloud, Meta, and Inception, with Prime Intellect expected soon. This failover process does not affect billing, as each model has a single published per-token price. You.com frames the Inference Router as a solution to stalled migrations of open-weight models into production. The service addresses security review concerns regarding zero data retention, US hosting, access controls, and data processing agreements (DPAs), which dedicated providers typically require large commitments to meet. Performance benchmarks on You.com’s LiveNewsBench indicate that open-weight models combined with You.com search can match frontier models at a lower cost. For example, GLM-5.3 with You.com search achieved 86.53% at $0.0485 per question, compared to Claude Sonnet 5.5 at $0.0920 per question, according to self-reported data.