What's new in Claude

Improved auto mode safety by blocking destructive git commands and adding infrastructure tool safeguards; added model deprecation warnings; fixed thinking block handling, WebSearch in subagents, and Windows Terminal rendering corruption.

Added /config key=value syntax for runtime settings, introduced sandbox.allowAppleEvents for macOS, improved streaming of long paragraphs, and fixed prompt caching on custom API gateways and Foundry.

Fixed mid-stream connection drops to preserve partial responses, resolved mouse-wheel scrolling in WSL2, and improved plugin loading performance in remote sessions.

/cd — move the current session to a new working directory mid-conversation without rebuilding the prompt cache.

Sub-agents can spawn sub-agents — background chains now supported up to five levels deep, enabling richer multi-agent orchestration.

--safe-mode — starts Claude Code with all customizations disabled, giving you a clean baseline for troubleshooting.

fallbackModel — configure up to three fallback models tried in order when the primary model is unavailable or hits limits.

Model retirements: claude-sonnet-4-20250514 and claude-opus-4-20250514 are retired — all requests now return errors. Upgrade to Sonnet 4.6 or Opus 4.8.

Tool versioning: New code_execution_20260521 exposes the 90-second per-cell limit in the tool description; new response_inclusion param on web search/fetch drops consumed result blocks from agentic API responses.

Claude Fable 5 launched — most capable widely released model, 1M token context window, 128k max output, always-on adaptive thinking, and a new stop_reason: "refusal" API response with no billing on pre-output refusals.

Managed Agents updates: Scheduled deployments now available (run sessions on a cron schedule); vaults support environment variable credentials for injecting secrets into agent sandboxes.

Claude Code and Claude Design now sync both ways — run /design-sync to pull your design system into your repo, or push what you've built back into Claude Design. Artifacts beta is also live: ask Claude to turn an active session into a shareable page that updates as it works.

Rate limits on Claude Code doubled and Opus API limits raised so developers and teams can build more reliably at scale. Claude Design's new design system import and canvas editing are now in sync with Claude Code via /design-sync.

Boris Cherny told Lauren Reeder he hasn't written a single line of code himself in 2026 — his whole team at Anthropic lives in Claude Code. He runs 5 instances simultaneously in separate git checkouts, numbered tabs 1–5, with system notifications for when Claude needs input. "Coding is effectively solved."

Thariq Shihipar posted about Todos turning into Tasks in Claude Code — the task system is getting a rework for better multi-agent coordination. No posts specific to the last 48h.