Daily AI news, sourcedOfficial news, first rumor reports and substantive progress. Each entry keeps the information published at that time.
- Anthropic details how Claude marks AI-generated content under the EU AI Act
Anthropic’s Claude Help Center explains marking commitments under the EU AI Act Code of Practice on transparency of AI-generated content: Claude models launched in the EU on or after August 2, 2026 will ship with machine-readable marks (embedded text watermarks and C2PA Content Credentials on supported files), marks apply across Claude Platform, Claude apps, Claude Code, Cowork, and Tag worldwide where supported, earlier models are in a transition period, and watermark detection is in private preview for eligible organizations.
- An unreleased Claude model failed to make a scorpion antivenom in a test with an investment firm, per The Verge
An investment research firm teamed up with Anthropic to test whether an unreleased version of Claude could make scorpion antivenom, hoping to show AI could transform drug development. It couldn't, The Verge reports.
- Anthropic takes Claude Opus 5.5 fast mode out of research preview so API users no longer need the beta header or access request
Anthropic's Fast mode docs say Claude Opus 5.5 fast mode is generally available: requests no longer need the fast-mode-2026-02-01 beta header (headers still work), and every usage tier gets a default fast-mode rate limit. Fast mode for Claude Opus 5 and Opus 4.8 stays in research preview. Use model claude-opus-5-5 with speed set to fast.
- Anthropic releases Claude Haiku 5.5, its fastest model yet, at about 75% lower running cost than Haiku 4.5
Anthropic launched Claude Haiku 5.5 for high-volume, cost-sensitive work such as summaries, classification, subagents, customer support and browser use. It is the first Haiku with adjustable effort levels and offers a 1M-token context window and up to 128k output tokens. Pricing is $0.10/$0.50 per million input/output tokens for prompts up to 100k tokens, and Anthropic reports 72.4% on OSWorld 2.1 and 39.2% on Terminal-Bench 4.0. Alongside it, Sonnet 5.5 cache reads drop 50% to $0.10 per million tokens. It is available now on the Claude Platform, AWS, Google Cloud and Microsoft Azure.
- Anthropic publishes a migration guide for moving from Claude Haiku 4.5 to Claude Haiku 5.5
Anthropic's new migration guide for Claude Haiku 5.5 lists the code changes from Haiku 4.5: swap the model ID, recount tokens because the same text uses more of them, switch extended thinking to adaptive, remove temperature, top_p and top_k, and replace assistant prefill with a user turn. In Claude Code, /claude-api migrate can apply the changes automatically.
- Claude Opus 5.5 and Sonnet 5.5 arrive on Amazon Bedrock in AWS GovCloud
AWS says Anthropic's Claude Opus 5.5 and Claude Sonnet 5.5 are available on Amazon Bedrock in the AWS GovCloud (US) Regions, and shows how to use them with Claude Code for compliance-aligned development on regulated and ITAR workloads.
- Anthropic adds thinking-output docs for Claude Fable 5 and Mythos 5
Anthropic's platform docs added a section on thinking output for Claude Fable 5 and Claude Mythos 5, per the documentation site.
- Anthropic lists introducing docs for Claude Fable 5 and Mythos 5
Anthropic's platform docs list an 'Introducing Claude Fable 5 and Claude Mythos 5' page under its models section, per the documentation site.
- Anthropic site lists Claude Fable and Mythos 5.1 pages
Pages titled 'Claude Fable and Mythos 5.1' appeared on Anthropic's site, suggesting an upcoming model or release; Anthropic has not announced details.
- Anthropic tightens Sonnet 5.5 thinking-block restrictions
Anthropic added another layer of restrictions to Sonnet 5.5's thinking blocks: thinking blocks generated by the model are now more constrained in how they can be used.
- Anthropic's Mike Krieger: Haiku 5.5 will round out the family in the coming weeks
Anthropic CPO Mike Krieger said on X that Haiku 5.5 will round out the Claude 5.5 family in the coming weeks.
- Anthropic releases Claude Sonnet 5.5, 30%+ faster than Sonnet 5 at the same price
Anthropic says Claude Sonnet 5.5, the second model in the Claude 5.5 family, generates output more than 30% faster than Sonnet 5 and costs up to 30% less per task for most work, at the same $2 per million input tokens and $10 per million output tokens. Anthropic says it scores 70.6% on Terminal-Bench 4.0, versus 10.3% for Sonnet 5, and lands two points below Opus 5.5 on GDPval-AA. It is available now, including on AWS, Google Cloud and Microsoft Azure and on the Claude Platform as claude-sonnet-5-5, and Claude Haiku 5.5 is due in the coming weeks.
- Claude Opus 5.5 is now available
Claude Opus 5.5 is now available, per Anthropic's site. AWS's Kiro team describes it as Anthropic's most capable Opus model yet, delivering Fable 5.1-level performance on most work at 40% lower cost.