Anthropic released Claude Code v2.1.290, introducing new fields for plugin hooks, tools for managing agent templates, and numerous bug fixes for stability and security.
- Added `serverToolUses` to the `turn.step` hook result and `agentId` to the `tool.check` event for better plugin context.
- Introduced `claude attach`, `claude logs`, and `/claude-api managed-agents-onboard` commands for session management and template creation.
- Fixed requests failing behind proxies that reject beta headers and resolved issues with long sessions getting stuck on unprocessable request errors.
- Addressed security concerns by fixing symlinked files loading outside working directories and image reads returning unauthorized paths.
- Resolved crashes from deep nesting, silent text dropping in WebFetch, and scheduled tasks not firing after compaction or hand-off.
These changes improve the reliability of complex agent workflows, enhance plugin development capabilities, and ensure stable operation across various network and session conditions.