Claude Code 2.1.310: one Windows hook fix, the rest for cloud sessions

Claude Code 2.1.310, released October 23, 2026, lands a day after 2.1.309 and shifts gears completely. Instead of a string of sandbox fixes, this version ships one more targeted permissions bug fix and spends most of its effort on enterprise cloud sessions. If you're not an admin, the fix to test is the Windows hook one; much of the rest is for teams running custom roles or using Claude Tag on Slack.

A Windows hook could let through a command it was meant to block

PreToolUse and PermissionRequest hooks intercept a tool call before it runs, to allow, deny, or rewrite it. On Windows, when Git Bash is missing from the machine and the hook's command is made only of quoted strings, such as a quoted path, Claude Code let the tool call through. In practice, a hook written to block a dangerous command blocked nothing in that specific case: the safety check a team had put in place was bypassed. 2.1.310 fixes this. If your hooks run on Windows machines where Git Bash isn't guaranteed to be installed, and you haven't checked lately, this is the one line in this changelog worth testing yourself.

The rest: cloud sessions, MCP, and a few reliability fixes

Everything else fits in a few lines. MCP elicitation, which lets a server ask for input in the middle of a tool call, gets a new error message: when the tool call times out in a non-interactive session while the question is still unanswered, Claude is now told that no answer came and not to repeat the call. On Bedrock, Vertex and Foundry, and when telemetry or nonessential traffic is disabled, the Monitor tool and plugin monitors are now available, and long foreground sleeps are now blocked there too. On the cloud sessions side, Enterprise organizations can now grant or revoke cloud sessions and Remote Control access separately per custom role, and turning either one on now asks for confirmation that lists the roles affected. Three reliability fixes stand out: requests failed behind some gateways and compatible servers that reject the effort-2025-11-24 beta value or mid-conversation system messages, and Claude Code now retries without them; automatic cleanup could delete recently pasted images when cleanupPeriodDays was set to a very high value; and compaction after a "Prompt is too long" error sometimes kept too much dense text, such as base64 or SVG, which could make the next request fail for the same reason. Most of the remaining fixes touch Claude Tag on Slack, the Code Review admin section, the VS Code extension, and cloud session dialogs: nothing that changes a habit if none of that applies to you.