Claude Code sessions on macOS and Linux can send messages to each other. Instead of manually copying information between terminals, Claude can fire off a text summary to another session. Anthropic says this works both ways. You can ask another session a question and get the answer back directly. Claude can also send a message on its own, say, if a change affects what another session is working on. The documentation lists typical use cases like sharing insights, coordinating parallel workflows, and checking status updates on long-running tasks.

On the same machine, communication happens locally. Between different computers, it routes through Anthropic's servers, and only responses are possible in that case. Admins can lock this feature down via settings. It's not available on Amazon Bedrock, Google Cloud Agent Platform, or Microsoft Foundry.

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