Message your other Claude Code sessions changedcross-session-messaging
Nearest release: v2.1.238, published 10 hours before this site recorded the change. Shown because the two are within 24 hours of each other. Nothing here says the release caused the edit.
Recorded here
Lines+11added
Lines−1removed
From line
59
where the diff opens
First seen
14 Aug 2026
this site's first read of the page
Recorded edits28to this page, all time
The whole hunk
from line 59, old and new numbered
/
from line 59
5959
6060The receiving Claude reads the message between tool calls during an active turn, so a running tool is never interrupted. When the receiving session is idle, Claude Code starts a new turn with the message.
6161
62Between two ordinary interactive sessions with default settings, Claude Code delivers the message. Delivery isn't guaranteed in every configuration, though. Claude Code refuses a message [over the size cap](#limitations) in the sending session, before it leaves. The receiving session checks each arriving message against its own [inbound controls](#control-inbound-messages), and the check ends in one of three outcomes:
62Claude Code refuses a message in the following cases:
6363
64* The message is [over the size cap](#limitations). Claude Code refuses it in the sending session, before it leaves.
65* A rapid burst to a session on this machine has reached [what that session's inbox accepts](#limitations). Claude Code refuses further messages to that session.
66* The reply target on this machine fails a safety check, such as a symlinked target or an endpoint that isn't the expected process. [Refusing to send a cross-session message](/docs/en/errors#refusing-to-send-a-cross-session-message) lists these checks.
67
68The receiving session checks each arriving message against its own [inbound controls](#control-inbound-messages), and the check ends in one of three outcomes:
69
6470* **Delivered**: Claude Code passes the message to the receiving Claude.
6571* **Held**: Claude Code sets the message aside undelivered. A held message reaches Claude only when you approve it or a later mode or settings change allows it.
6672* **Refused**: Claude Code drops the message without delivering it.
from line 113
107113* **Your cloud sessions**: your [Claude Code on the web](/docs/en/claude-code-on-the-web) sessions, shown while this session is connected to [Remote Control](/docs/en/remote-control). Claude Code labels them `cloud` in the listing.
108114* **Your Remote Control sessions on other machines**: shown while this session is connected to [Remote Control](/docs/en/remote-control), and labeled `Remote Control`. Claude Code shows `offline` as the status of a session whose Remote Control connection has dropped.
109115
116Claude Code reads your cloud and Remote Control session lists newest first and stops after a bounded number of pages for each. If your account has more of those sessions than fit, Claude Code doesn't list the older ones, and Claude can't message them by name. When this happens, Claude Code says so in the listing, and Claude sees the same note when it sends a message.
117
110118Claude addresses a session beyond this machine by name, the same as a local session. See [Message sessions on other machines](#message-sessions-on-other-machines) for how those messages travel.
111119
112120A session answers to the name you set with the [`/rename`](/docs/en/commands) command or the [`--name`](/docs/en/cli-reference#cli-flags) flag. When you don't set one, Claude Code names the session itself. For an interactive session, Claude Code derives the name from the working directory's folder name, such as `my-app-3f` in a `my-app` directory.
from line 289
281289 * **Inbound controls**: the [receiving session's inbound controls](#control-inbound-messages) can hold or drop what you send it.
282290 * **Cloud session missing**: a cloud session appears only while this session is connected to [Remote Control](/docs/en/remote-control).
283291 * **Other-machine session missing**: a session on another of your machines appears only when it runs with [Remote Control](/docs/en/remote-control) and this session is connected as well.
292 * **Older cloud or other-machine session missing**: Claude Code [reads those session lists newest first and stops after a bounded number of pages](#see-which-sessions-claude-can-reach), so Claude can't message a session that fell past them by name.
284293 * **Starting a conversation**: [Message sessions on other machines](#message-sessions-on-other-machines) covers starting a conversation with a session beyond this machine.
285294
286295In a session with messaging, `/status` also shows a `Peer address` row with the session's own inbox address.
from line 300
291300
292301* **Plain text only**: Claude sends only plain text across sessions. Structured [agent team](/docs/en/agent-teams) protocol messages stay within a team.
293302* **Same-machine message size is capped**: Claude Code refuses a message to a session on this machine once its serialized form passes about a million characters. The refusal [names the exact sizes](/docs/en/errors#message-too-large-for-cross-session-delivery). Nothing reaches the receiving session.
303* **Rapid bursts to one session are refused at the sender**: once a rapid burst of messages to a session on this machine reaches what that session's inbox accepts, Claude Code refuses further sends in the sending session. The [refusal names the burst](/docs/en/errors#too-many-messages-to-this-session-just-now) and tells Claude to batch the rest into one message or wait. Before v2.1.236, Claude Code reported those sends as sent while the receiving session dropped them.
294304* **Message loops are throttled**: in the receiving session, Claude Code rate-limits repeated messages per sender, drops identical repeats arriving within a short window, and queues at most 50 accepted messages for Claude to read. A message loop between two sessions therefore stops on its own. When the rate limit, repeat check, or queue cap drops a message from an interactive session on this machine, Claude Code tells that session which one dropped it and tells its Claude not to resend right away.
295305
296306## Related resources
No line in this hunk matches that.