anthropic-sdk-python v1.8.0 adds claude-opus-5-5 and tool features
Release v1.8.0 (2026-09-22) adds support for claude-opus-5-5, inline tool definitions and MCP tool-list pinning (beta); includes multiple bug fixes, docs updates and internal changes.
What changed
Added support for claude-opus-5-5, inline tool definitions and MCP tool-list pinning (beta); bug fixes for evaluated_permission enum, Python 3.13 streaming exit crash, add_tools() behavior and tool runner compaction.
Why it matters
Developers can integrate the new model and tool flows into apps; teams running Managed Agents and streaming workloads should see more stable runtime and permission consistency.
Who should care
DevelopersEnterprises
Worth trying
Yes — Access claude-opus-5-5 and inline tools; includes streaming and add_tools() fixes.