isolatePeerMachines
A Claude Code settings key, read out of the shipped bundle. It was in the build from v2.1.138 and was gone by v2.1.284.
Ask you before Claude messages one of your sessions on another machine
Anthropic's own wording. Read off All settings, captured 2026-10-22.
In the changelogs
13Releases whose published page names isolatePeerMachines.
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v2.1.287
Sending a message to a session on another machine can always require approval
Claude Code can now ask for your approval before a message goes to another machine, even when
isolatePeerMachinesis offfound in this entry's text, named in this entry
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v2.1.269
SendMessage cross-machine permission check now passes a detached
askcallbackSendMessage's cross-machine permission check now uses a detached approval callback instead of passing context and canUseTool directly
found in this entry's text
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v2.1.268
New bypass-immune classifier category: denyRulesUnjudged
A new denyRulesUnjudged permission category bypasses classifier judging but still can't be bypassed by rules
found in this entry's text
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v2.1.225
send_message: clearer story about sessions on other machines
Messaging an unknown peer now explains that sessions on other machines could not be checked, so retry.
found in this entry's text
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v2.1.224
Cross-machine messages ask first when peer isolation is on
With isolatePeerMachines on, cross-machine messages now stop and ask for your approval.
named in this entry, found in this entry's text
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v2.1.224
SendMessage can address other sessions directly and reports delivery timing
Messages can be addressed to a specific session by socket or id, blocked unless peer messaging is enabled.
found in this entry's text
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v2.1.223
Circuit-breaker permission reasons moved to a registry; isolatePeerMachines is now bypass-immune
Cross-machine file transfer denials can no longer be bypassed once you enable peer isolation.
named in this entry, found in this entry's text
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v2.1.223
Circuit breakers carry declared traits instead of hard-coded name checks
Peer-machine isolation prompts now survive bypass permissions mode and are never auto-approved.
named in this entry, found in this entry's text
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v2.1.223
Permission circuit breakers now have a capability table
Peer-machine isolation prompts now still appear even when you're running in bypass-permissions mode.
found in this entry's text
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v2.1.210
SendFile — Send Files Between Claude Code Sessions
found in this entry's text
- v2.1.124
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v2.1.124
isolatePeerMachinessetting (Remote Control safety)found in this entry's text
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v2.1.124
Session resume tracks isolation latch
found in this entry's text
First cited
4The earliest release whose published evidence quoted isolatePeerMachines was v2.1.124, 30 Apr 2026. That is the oldest release this project wrote about it, so it is a floor on the name's age and not the release that introduced it. It is not a presence reading: which builds carried the name is the table below.
Presence across releases
2Build by build
149One row per release since the first build this name was read out of. Absent means the build was read and the name was not in it, never mined means no bundle for that release was ever archived, and a declared type or a default is only ever what that release's own bundle stated.
Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the settings key does. All settings keys.