release

Claude Fable 5.2 and Claude Mythos 5.2 models released for advanced reasoning

docs.claude.comagent

Anthropic released Claude Fable 5.2 and Claude Mythos 5.2, new models built for demanding reasoning and long-horizon agentic work with 1M token context and always-on adaptive thinking. These models enforce prefix check validation, require the new computer_toolset_20260801, and can read other Claude 5 models' thinking blocks, though their own thinking blocks are model-exclusive.

Stacks this affects

Claude ships in 34 tested stacks here.

Full-stack with Lovable
Code · Builder
$70/mo
Cloud IDE with Replit
Code · Builder
$40/mo
UI-first with v0
Code · Builder
$60/mo
AI newsletter
Writing · Newsletter
$80/mo
AI newsletter (Substack)
Writing · Newsletter
$53/mo
AI thumbnails + ad creative
Marketing · Visual
$50/mo
Android app with AI
Code · Mobile
$42/mo
Autonomous research agent
Research · Intelligence
$59/mo
Cheap bulk LLM automation
Code · Backend
$140/mo
Cold outbound
Sales · Outbound
$342/mo
Cold outbound (solo)
Sales · Outbound
$75/mo
iOS + Android with Expo
Code · Mobile
$67/mo
Faceless YouTube
Video · Creator
$92/mo
Faceless YouTube (budget)
Video · Creator
$6/mo
Inbox triage
Productivity · Inbox
$51/mo
Inbox triage (free)
Productivity · Inbox
$26/mo
Indie SaaS
Code · Builder
$75/mo
Indie SaaS (Gemini long-context)
Code · Builder
$75/mo
iOS app with AI
Code · Mobile
$48/mo
LinkedIn ghostwriting
Writing · Agency
$129/mo
LinkedIn (for yourself)
Writing · Personal
$33/mo
Live trend research
Research · Intelligence
$70/mo
Multilingual content factory
Writing · Content
$60/mo
Open-weight LLM stack
Code · Backend
$170/mo
SEO content engine
Writing · SEO
$118/mo
Antigravity (Google)
Code · Workflow
$40/mo
Codex (CLI + cloud)
Code · Workflow
$40/mo
Ship code with AI
Code · Workflow
$50/mo
Cross-platform short-form
Marketing · Distribution
$49/mo
Self-hosted scheduler
Marketing · Distribution
$25/mo
TikTok character
Video · Creator
$92/mo
TikTok character (audio + text)
Video · Creator
$42/mo
UGC ad creative
Marketing · Ads
$67/mo
UGC ads (CapCut-only)
Marketing · Ads
$24/mo
All Claude changes and pricing

More Claude

featureSelf-hosted Claude Managed Agents service now availablereleaseClaude Fable 5.2 and Claude Mythos 5.2 released with reasoning and long-context capabilitiesreleaseClaude Fable 5.2 and Claude Mythos 5.2 launched with 1M context window and always-on adaptive thinkingfeatureFast mode for Claude Fable 5.2 delivers 2.5x faster output tokens per secondfeatureIP allowlist for organizations restricts API access to whitelisted addresses