AI Toolbox, a browser extension for ChatGPT and Gemini, now supports Claude Opus 5, replacing two separate paid extensions with a single tool that offers folders, search, prompt templates, bulk export…
Anthropic launched Claude Opus 5, achieving an ECI of 159 and matching Fable 5 on SWE-ECI at 161, according to Epoch AI Research. Independent evaluations show Opus 5 outperforming Fable in coding and …
Anthropic's Claude Opus 5 API introduces three new behaviors: an effort toggle with five levels controlling reasoning depth and cost, a Fast Mode delivering 2.5x speed at six times the standard price,…
Anthropic quietly shipped Claude Opus 5 last week, offering roughly 33% lower cost than Opus 4 with improved code generation and tool-calling reliability. A developer who tested the model on a cross-b…
Anthropic launched Claude Opus 5, a model that matches or beats its flagship Fable 5 at half the cost, topping third-party leaderboards. Meanwhile, Microsoft, Meta, and Nvidia led a 20-company coaliti…
Anthropic released Claude Opus 5, which topped the Artificial Analysis Intelligence Index at 61, with Fable 5 and GPT-5.6 Sol within a point or two, at roughly half Fable's cost and without Fable's 30…
Anthropic launched Claude Opus 5 on July 24, 2026, at $5 per million input tokens and $25 per million output tokens, half the cost of its own Fable 5 model, while matching output quality and using one…
Anthropic's Claude Opus 5, released July 24, 2026, introduces an 'effort' parameter that lets developers trade cost for reasoning capability. The parameter has five levels—low, medium, high (default),…
Anthropic released Claude Opus 5 on July 24, scoring 30.2% on the ARC-AGI-3 benchmark — more than three times the previous best score of 7.8% by GPT-5.6 Sol — and beating Fable 5 on agentic terminal c…
Anthropic released Claude Opus 5 on July 24, offering near-Fable-5 performance at the same pricing as Opus 4.8 ($5 per million input tokens, $25 per million output tokens), deliberately cannibalizing …
A new structured AI research workflow called 'source-first architecture' improves output fidelity by breaking queries into granular questions, extracting raw snippets with metadata, resolving source c…
Anthropic's Claude Opus 5 is closing the gap with Mythos-class model Fable 5 on complex coding tasks, according to developer benchmarks. In tests on asynchronous race conditions in TypeScript, Opus 5 …
Anthropic PBC launched Claude Opus 5, a large language model that approaches the output quality of its top-end Mythos 5 algorithm in many areas but costs significantly less, and is now the default mod…
Boris Cherny, an Anthropic employee, stated that Claude Opus 5 is the company's least prompt-injectable model yet, based on prompt injection evaluations and red teaming results detailed in the system …
Anthropic released Claude Opus 5, priced at half the cost of Fable 5 while outperforming it on most benchmarks, including a perfect 42/42 on IMO 2026. However, the model's 193-page system card reveals…
A new paper finds that long chain-of-thought reasoning in AI models often fails to converge on an answer, with many traces lost long before they stop talking. The analysis, from researchers studying t…
Amazon Web Services launched Anthropic's Claude Opus 5 on Amazon Bedrock on 24 July 2026, pricing the model at $5 per million input tokens and $25 per million output tokens — half the cost of the flag…
A coalition of 25 tech companies led by Nvidia, Microsoft, and Meta warned against overregulating open-weight AI models, exposing a divide with proprietary model companies like OpenAI and Anthropic. M…
Anthropic's system card for Claude Opus 5 reports a 41% self-estimated probability that the model qualifies as a 'moral patient,' an entity whose experiences deserve ethical consideration. The model a…
Anthropic's per-model prompting pages serve as a maintenance list for instruction files like CLAUDE.md, which become stale after each model release because new models interpret prompts more literally,…