anthropic-sdk-python v1.12.0: adds claude-haiku-5-5 and toolset updates
v1.12.0 (2026-10-07) adds model claude-haiku-5-5, typed computer and browser toolset tool calls, model lifecycle and line fields, url_sources, web search and code execution support, RBAC display_name, and docs note agent tools limit 256.
What changed
Added claude-haiku-5-5; typed computer and browser toolset tool calls; model lifecycle and line fields; url_sources and web search and code execution support; RBAC display_name; docs state agent tools limit as 256.
Why it matters
Developers can integrate the new model and typed tool calls into agent/tool workflows and use web search and code execution capabilities.
Who should care
DevelopersEnterprisesResearchers
Worth trying
Yes — use claude-haiku-5-5 and typed tool calls in current agents