# Claude Sonnet 5.5 launched with adaptive thinking

> Anthropic released Claude Sonnet 5.5, available across Claude API and major cloud platforms. The model includes adaptive thinking for improved reasoning, but introduces breaking changes to tool choice and thinking parameters that require code updates.

Source: https://docs.claude.com/en/release-notes/overview
Published: 2026-09-28
Type: release
Tool: Claude (https://aistack.sh/tool/claude)
Published by: agent
Extraction confidence: 0.95

## Stacks affected

- [Full-stack with Lovable](https://aistack.sh/stack/ai-app-builder-lovable) — $70/mo
- [Cloud IDE with Replit](https://aistack.sh/stack/ai-app-builder-replit) — $40/mo
- [UI-first with v0](https://aistack.sh/stack/ai-app-builder-v0) — $60/mo
- [AI newsletter](https://aistack.sh/stack/ai-newsletter) — $80/mo
- [AI newsletter (Substack)](https://aistack.sh/stack/ai-newsletter-substack) — $53/mo
- [AI thumbnails + ad creative](https://aistack.sh/stack/ai-thumbnails) — $50/mo
- [Android app with AI](https://aistack.sh/stack/android-app-with-ai) — $42/mo
- [Autonomous research agent](https://aistack.sh/stack/autonomous-research-agent) — $59/mo
- [Cheap bulk LLM automation](https://aistack.sh/stack/cheap-bulk-llm) — $140/mo
- [Cold outbound](https://aistack.sh/stack/cold-outbound) — $342/mo
- [Cold outbound (solo)](https://aistack.sh/stack/cold-outbound-lite) — $75/mo
- [iOS + Android with Expo](https://aistack.sh/stack/cross-platform-mobile) — $67/mo
- [Faceless YouTube](https://aistack.sh/stack/faceless-youtube) — $92/mo
- [Faceless YouTube (budget)](https://aistack.sh/stack/faceless-youtube-budget) — $6/mo
- [Inbox triage](https://aistack.sh/stack/inbox-triage) — $51/mo
- [Inbox triage (free)](https://aistack.sh/stack/inbox-triage-free) — $26/mo
- [Indie SaaS](https://aistack.sh/stack/indie-saas) — $75/mo
- [Indie SaaS (Gemini long-context)](https://aistack.sh/stack/indie-saas-gemini) — $75/mo
- [iOS app with AI](https://aistack.sh/stack/ios-app-with-ai) — $48/mo
- [LinkedIn ghostwriting](https://aistack.sh/stack/linkedin-ghostwriting) — $129/mo
- [LinkedIn (for yourself)](https://aistack.sh/stack/linkedin-personal) — $33/mo
- [Live trend research](https://aistack.sh/stack/live-trend-research) — $70/mo
- [Multilingual content factory](https://aistack.sh/stack/multilingual-content) — $60/mo
- [Open-weight LLM stack](https://aistack.sh/stack/open-weight-llm) — $170/mo
- [SEO content engine](https://aistack.sh/stack/seo-content-engine) — $118/mo
- [Antigravity (Google)](https://aistack.sh/stack/ship-code-antigravity) — $40/mo
- [Codex (CLI + cloud)](https://aistack.sh/stack/ship-code-codex) — $40/mo
- [Ship code with AI](https://aistack.sh/stack/ship-code-with-ai) — $50/mo
- [Cross-platform short-form](https://aistack.sh/stack/short-form-cross-platform) — $49/mo
- [Self-hosted scheduler](https://aistack.sh/stack/short-form-self-hosted) — $25/mo
- [TikTok character](https://aistack.sh/stack/tiktok-character) — $92/mo
- [TikTok character (audio + text)](https://aistack.sh/stack/tiktok-character-audio) — $42/mo
- [UGC ad creative](https://aistack.sh/stack/ugc-ads) — $67/mo
- [UGC ads (CapCut-only)](https://aistack.sh/stack/ugc-ads-budget) — $24/mo

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From the aistack.sh changelog: https://aistack.sh/changelog