Anthropic SDKs and ant CLI default to new 2026-10-21 API version
ClaudeDevs · x · 2026-10-22
New major versions of all Anthropic SDKs and the ant CLI default to API version 2026-10-21. The migration guide lays out three steps: upgrade the SDK (e.g. anthropic 2.0.0 for Python) or set the anthropic-version header, fix breaking changes (document blocks in assistant messages and citations in user messages now 400), and test before release. Claude Code users can update via the /claude-api skill.
Related event: Claude API Ships First New Version Since 2023 with Breaking Changes(3 posts)→
More from coding & agent
- "My job is telling Claude to think bigger"—devs joke about AI ambition gap — paulnovosad · 2026-10-22
- Superset MCP Server Lets LLMs Query Apache Superset via REST API — modelcontextprotocol · 2026-10-22
- Crates MCP Connector Wraps crates.io REST API, Free and Auth-Free — modelcontextprotocol · 2026-10-22
- Ropedia's S-Agent 2.0 Tops Spatial Reasoning Benchmarks With Zero Training, Scoring 66.5 on MMSI — CyberRobooo · 2026-10-22
- Eden Deploys Vercel's Eve Agent to Cloudflare With One Command, Fully Open Source — ritakozlov · 2026-10-22
- Ben Bajarin: rambling research notes into AI for organized workshop analysis works well — BenBajarin · 2026-10-22