anthropic-sdk-python v0.121.0 repo
anthropic-sdk-python v0.121.0 (released August 7, 2026) adds four new API capabilities: (1) mid-conversation-tool-changes-2026-07-01 beta, enabling tool addition and removal during an ongoing conversation turn without starting a new session; (2) session budgets, per-session token spend caps set at the API level before a session begins; (3) an advisor tool, a structured tool that surfaces model reasoning steps as inspectable, logged data rather than free-text; and (4) pinned inference location, routing requests to a specific geographic region for latency or compliance requirements. It also adds skills auto-loading from GitHub, meaning Claude Code and Hermes can specify a GitHub repo URL and the SDK pulls skill definitions from it at session start. The release removes retired Claude Opus 4.1 models from the model list.
What it does for you: Skills auto-loading from GitHub means Hermes can point at yanyiooi-ux/axion-skills and load skills directly at session start, replacing the current manual sync-skills.py step that runs nightly. Session budgets give YY API-level cost control per Hermes bridge session without relying on ad-hoc token counting in the bridge code. The advisor tool exposes model reasoning steps in a structured format, enabling the night-shift queue to log decision evidence for each task processed. Upgrade is one command: pip install -U anthropic.
In practice: critical-sdk-update-skills-autoload-session-budgets
For: Hermes. Direct Hermes dependency; v0.121.0 adds skills auto-loading from GitHub and session budgets that wire into the Axion bridge without any adapter layer.
Verdict: build now. Skills auto-loading from GitHub directly replaces the current manual nightly skill sync. Session budgets add API-level cost control the bridge currently lacks. Upgrade is pip install -U anthropic and the feature set is immediately wirable without new infrastructure.
Build #1 anthropic-sdk-python v0.121.0: use the ai-implementation-build-intake skill to build this safely. Source: https://github.com/anthropics/anthropic-sdk-python/releases/tag/v0.121.0. Save canonical skill/agent under AXION\Skills and AXION\Agents.
Source · anthropics/anthropic-sdk-python v0.121.0 release tag confirmed August 7, 2026. Mid-conversation-tool-changes-2026-07-01 beta confirmed in commit c7d1531. Session budgets, advisor tool, pinned inference location, and skills auto-loading from GitHub confirmed in commit 193bae0. Retirement of Claude Opus 4.1 models confirmed in commit 5352a33. Version v0.121.0 confirmed as Latest release.