Claude Code Adds Cross-Session Messaging

Anthropic documents several intended uses for the feature:

• •Passing a finding or decision from one session to another session affected by it.
• •Coordinating work in separate Git worktrees for the same repository.
• •Requesting status from long-running work, such as migrations or test runs.
• •Replying to a message received from a Claude Code session on another machine or through Remote Control.

The cross-machine behavior is limited. Anthropic's documentation states that a session on another machine or on the web can reply to an existing exchange, but cannot initiate one. Within an individual session or team, SendMessage can also address subagents and teammates.

9to5Mac reported that the update is designed for users running multiple Claude Code sessions simultaneously, particularly where separate sessions are working on different areas of one project. Anthropic's documentation gives an example in which one session can warn another after a change breaks an assumption in the second session's work, or send an answer after resolving a question that had blocked another task.

Cross-session messages do not bypass Claude Code's action-approval model. 9to5Mac reported that messages cannot approve permission requests or change configurations. Commands such as /compact arrive as plain text, rather than being executed as commands, and a receiving session still asks the user for approval if acting on a message needs permission.

Classmethod's testing report on v2.1.224 describes new crossSessionInbound and dialogExpiry settings. It reports that messages sent to a running session that would bypass permissions are held pending approval, while messages to other sessions are delivered automatically. The same report characterizes the release as containing 31 changes, including a new self-hosted runner capability and Remote Control-related updates, although those features are separate from cross-session messaging.

For engineering teams, the practical value is less about shared agent memory than about reducing manual relay work between independently steered sessions. In comparable multi-agent workflows, explicit message passing can help communicate repository-level changes and unblock parallel tasks, but it also leaves important controls intact: messages are not file transfers, do not carry entire chat histories, and cannot silently authorize privileged operations. Teams using multiple worktrees or long-running agent tasks can therefore evaluate the feature as a coordination channel rather than as a replacement for source control, review, or permission boundaries.