We've released API version 2026-10-21
By Steven Van ·
Python, TypeScript, Go and other SDKs plus the ant CLI move to new major versions, now under Apache 2.0, and user profiles gain enforcement fields.
Anthropic has released API version 2026-10-21, along with new major versions of its client SDKs and the ant CLI that send that version by default. The release note points to a migration guide, "Migrating to API version 2026-10-21", for upgrading.
New SDK and CLI versions
- Python SDK 2.0.0
- TypeScript SDK 1.0.0
- C# SDK 13.0.0
- Go SDK 2.0.0
- Java SDK 3.0.0
- PHP SDK 1.0.0
- Ruby SDK 2.0.0
- ant CLI 2.0.0
These releases also include breaking changes that don't depend on the API version. They are now licensed under Apache 2.0 instead of the MIT License.
Enforcement status on user profiles
User profiles now have enforcement_status and enforcement_actions fields, so an API customer can see whether Anthropic has restricted or banned one of their end customers. Listing profiles with the new enforcement_status[] filter returns the ones that have an open restriction or ban.
The Anthropic docs page the release note links to is the CLI quickstart, which covers installing and authenticating the ant CLI. It installs through Homebrew on macOS, a release binary on Linux and WSL, or go install, and ant auth login starts a browser-based OAuth flow against the Claude Console.