Claude Code v2.1.224 adds self-hosted environments, cross-session messaging, and archive plugin installation

Anthropic released Claude Code v2.1.224, which adds self-hosted environments via a new claude self-hosted-runner component that lets teams run Claude Code sessions on their own machines or containers on Team and Enterprise plans.

The update introduces an archive plugin installation method that allows users to install plugins from a ZIP archive over HTTPS without requiring git or npm, with optional SHA-256 pinning for integrity verification.

Claude Code sessions can now send messages to each other across machines using a new SendMessage capability, and users can discover available agents with the ListAgents command.

Sandbox credential-masking options were expanded to include extract and onExtractNoMatch for structured environment values, decode: "jwt" with maskClaims for JWT-aware masking, and awsPairs / sigv4 for AWS SigV4 re-signing; these features require network.tlsTerminate and are honored only from user, managed, or --settings contexts.

The release addresses a bug where long project paths (>200 characters) could resolve to another project’s session directory under a shared sanitized prefix, and fixes session list, rename, fork, delete, and /resume operations to prevent cross-project interference.

Remote Control reliability was improved with fixes for auto-start failures, blank post-clear messages, and stale session handling, alongside better progress reporting and reconnection UX for attached clients.

VS Code extension users received fixes for Remote Control connection state visibility and a bug where sessions resumed despite Remote Control being disabled.

The changelog also notes removal of the 200-subagent-per-session spawn cap, improved fullscreen history retention, and changes to managed settings and feedback survey transcript sharing behavior.