Claude Code version 2.1.273 introduces new request headers for LLM gateways, enhances session management features, and resolves numerous permission and connectivity bugs across desktop, web, and Slack integrations.
- Added opt-in request headers (e.g., `x-claude-code-request-class`) for LLM gateways via `CLAUDE_CODE_GATEWAY_HINT_HEADERS=1`.
- Fixed critical issues where Bash commands skipped prompts under `permissions.blockReadsOutsideWorkingDirectories` and sub-agents were incorrectly reported as failed.
- Improved error messaging for MCP server disconnections, cloud session creation failures, and GitHub authentication issues to provide specific remediation steps.
- Resolved bugs affecting VS Code banners, Windows UNC path permissions, and Claude Tag's handling of Enterprise Grid and AWS connections.
These changes improve security analysis accuracy, enhance troubleshooting clarity for network and permission errors, and stabilize background task execution.