Claude Code sessions can now message each other directly

Claude Code sessions on macOS and Linux can now talk to each other. Per the week 32 changelog, a session finds other local sessions with the ListAgents tool and sends them plain text through SendMessage, either because you ask it to or because it decides on its own that a change in one session affects work happening in another. The docs are specific about the limits: it passes written text only, never conversation history or files. Run /list-agents and you'll see which sessions are reachable.

The bigger change lands August 14. Auto mode becomes the default permission mode for new Pro, Max, and Team sessions, and the classifier calls that decide what auto mode allows stop counting toward usage limits. That second part is the one worth watching. Anthropic is removing the meter from the exact mechanism that governs what Claude can do without asking first, which lowers the cost of running it in a more autonomous stance by default.

A few smaller items shipped alongside these. The 200-subagent-per-session cap is gone. The /fork command runs in its own worktree. And worktree isolation, which used to cover file edits, extends to Bash commands and git redirects too.

Taken together, this is Anthropic building for a workflow where multiple sessions run at once and need to coordinate, not just execute one task each in isolation. If you're running parallel sessions on a shared codebase, cross-session messaging replaces some of the manual copy-pasting between terminal tabs. Check whether your worktree setup depended on the old, narrower isolation boundary, since Bash commands and git redirects are now covered too.