Claude Haiku 5.5 release watch and what Anthropic has said
Anthropic said Haiku 5.5 would arrive in the coming weeks on September 28. The exact date, pricing and public access details remain unconfirmed.
Anthropic
Anthropic news and analysis covering Claude, developer tools and AI research. Follow model access, product changes and release plans with clear distinctions between company announcements and independent observations.
Claude Code tightens permission checks during plugin restarts
Claude Code 2.1.292 repairs plugin permission checks and uses base branch CLAUDE.md rules when a pull request edits them.
Claude Models API adds a check for turning thinking off
Developers can inspect support before selecting a thinking configuration.
ThinkingBox tests repeatability of Claude Opus 5.5
ThinkingBox compares average completion and repeated success
Antigravity adds Claude 5.5 access and dates older model removals
Antigravity lists paid Claude 5.5 access and November 2 removals
Sonnet 5.5 enters Agent Arena with a task cost tradeoff
New Agent Arena results place Sonnet 5.5 near the top while showing why effort settings and measured task spending matter alongside token prices.
Anthropic sets November 30 deadline for Claude Sonnet 4.5
Claude Sonnet 4.5 remains available until its November 30 retirement. Anthropic recommends Sonnet 5.5 and gives developers a migration checklist.