Claude Code v2.1.219 introduces Claude Opus 5 as the new default Opus model, featuring a 1M context window and fast mode pricing of $10/$50 per Mtok. The update also enables nested subagent forwarding in stream-json and increases the maximum nesting depth to 3 by default.
- Added Claude Opus 5 (claude-opus-5) as the default Opus model with 1M context and fast mode at $10/$50 per Mtok.
- Added sandbox.network.strictAllowlist setting to deny non-allowlisted hosts for sandboxed commands without prompting.
- Added DirectoryAdded hook that fires after /add-dir or SDK register_repo_root registers a new working directory mid-session.
- Added nested subagent forwarding in stream-json, allowing subagents spawned at depth-2+ to appear when --forward-subagent-text is set.
- Changed dynamic workflows to default to a medium size guideline (aim for fewer than 15 agents).
- Subagents can now spawn nested subagents up to depth 3 by default; set CLAUDE_CODE_MAX_SUBAGENT_SPAWN_DEPTH=1 to disable nesting.
These changes provide users with access to the latest Opus model capabilities and more granular control over sandboxed environments and agent workflows.