Claude Haiku 5.5 is now generally available in GitHub Copilot

Anthropic's Claude Haiku 5.5 is now generally available across GitHub Copilot, accessible in the GitHub Copilot app, the CLI, and code. GitHub positions the lightweight model for fast, high-volume workloads, including subagents, quick code edits, and terminal tasks.

According to GitHub, early testing detailed in its [changelog](https://github.blog/changelog/2026-10-07-claude-haiku-5-5-in-github-copilot/) showed that Claude Haiku 5.5 matched Claude Sonnet 5 on many coding tasks while requiring significantly fewer tokens and steps.