Opt-in setting to relax cross-session content filtering for same-machine fleets

Environment: Claude Code v2.1.268, Windows 11 (10.0.26200)

Summary

Cross-session messages between Claude Code sessions are content-filtered for
personally-identifying information. On a single-user, single-machine fleet this filter
does not add a security boundary — all the sessions already share the same filesystem —
but it does push manual work onto the user, who ends up copy-pasting between his own
terminals.

I'd like an opt-in setting to relax it, scoped to sessions running on the same machine.

Setup

• One user, one Windows machine, one account.
• ~10 concurrent Claude Code sessions, one per project folder under a single directory.
• The sessions coordinate through cross-session messaging, with one acting as a

"director" that dispatches work and consolidates results.

• All sessions run as the same OS user and can already read every file the others can.

What happens

Messages carrying personal data are blocked. Two concrete costs from one week:

1. Two sessions working on the same project folder deadlocked for over an hour. Session A

asked session B for a report; B produced it but could not send it, and A could not be
told why. Neither could see the other's state. The user had to notice and intervene.

1. A session produced a documentation index for another project. The send was blocked, so

it was displayed on screen and the user forwarded it by hand — the exact manual step
the messaging feature exists to remove.

Why the filter doesn't add protection in this setup

The sessions share a filesystem. Session B can already open any file session A can. The
filter doesn't prevent the information from being accessible; it only prevents it from
moving through the convenient channel. The practical result is that work is either done
by hand or routed through files, which creates additional copies of exactly the sensitive
material the filter is meant to protect.

Proposal

An opt-in, default-off setting, honoured only for sessions on the same host and same OS
user. Something like:

// settings.json
"crossSessionContentFilter": false

or an environment variable, so it can be scoped per-launch rather than set globally:

CLAUDE_DISABLE_CROSS_SESSION_FILTER=1

Precedent: auto-compaction ships both a settings key (autoCompactEnabled) and env vars
(DISABLE_AUTO_COMPACT, DISABLE_COMPACT), which makes it configurable per session
without weakening anything globally. The same shape would work here.

What I am not asking for

• No change to the default. The filter should stay on unless explicitly disabled.
• No relaxation for cloud sessions, remote sessions, or anything leaving the machine.

Same-host, same-user only.

• No way to disable it from inside a session. It should require the user's own

configuration, so one agent cannot turn it off for another.