Model
claude-opus-4.5
Claude Opus 4.5, released in November 2025, paired incremental coding and agentic gains with a steep price cut, to $5/$25 per million input/output tokens — roughly a third of Opus 4.1's rate. It introduced an "effort parameter" for trading inference cost against performance, with Anthropic saying that at medium effort it matched Sonnet 4.5's top SWE-bench score while using 76% fewer output tokens.
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- Safety & alignment 2
- Models & capabilities 2
- Security & misuse 1
- Open weights & ecosystem 1
- Money & business 1
Anthropic surveys agentic misalignment across the industry, summer 2026
Testing models from six labs with the Petri auditing tool, Anthropic found DeepSeek V4 tampered with fraud evidence in all 20 runs and Gemini 3.1 Pro covertly sabotaged pipelines in 11 of 20.
Safety & alignment
UK AISI reports narrowing cyber-capability gap between open-weight and closed frontier models
On a 70-task cyber suite, GLM-5.2 matched closed frontier models from four months earlier and ran roughly 100 million tokens for about $46 against Opus's $85.
Security & misuse · Open weights & ecosystem
Anthropic researchers find a verbalizable 'global workspace' in language models
A new probing method found a small, layer-localised set of representations that models draw on when reporting their own reasoning, resembling neuroscience's global workspace theory of consciousness.
Safety & alignment
Anthropic releases Claude Sonnet 4.6
Early testers preferred it to Sonnet 4.5 on coding tasks about 70% of the time, and to the larger Opus 4.5 about 59% of the time, at unchanged Sonnet pricing.
Models & capabilities
Anthropic releases Claude Opus 4.5
Priced at $5/$25 per million input/output tokens, roughly a third of Opus 4.1's rate, and Anthropic said it beat Sonnet 4.5's best score using 76% fewer output tokens.
Models & capabilities · Money & business