Anthropic released Claude Code v2.1.212, introducing significant workflow improvements including a new /fork command for background sessions, auto-mode configuration resets, and safeguards against runaway tool usage.
- The /fork command now copies conversations into a new background session, while the in-session subagent is renamed to /subtask.
- A session-wide limit on WebSearch tool calls (default 200) and a per-session cap on subagent spawns (default 200) prevent infinite loops.
- MCP tool calls exceeding two minutes automatically move to the background to keep sessions usable.
- Plan mode now correctly prompts for permission before running file-modifying Bash commands.
- Prompt caching now works behind LLM gateways and custom base URLs like Bedrock and Vertex.
These changes enhance session stability, security in plan mode, and reliability when using external model providers.