[BUG] Parrallel Claude Code Session Starts when Remote Control Invoked from Claude Code Desktop GUI

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Summary

Invoking Remote Control from a desktop session resulted in a *second, independently
executing* session (on the phone) rather than a passive mirror. Both sessions ran the
same long-running agent task against the same local git working tree/branch
simultaneously. Neither the desktop GUI nor the desktop agent had any indication the
other session was running and editing files — the collision was only detectable through
git history and filesystem side-effects.

Severity

High — silent concurrent writes to one working tree: racing/duplicate commits,
clobbered edits, corrupted shared state, potential data loss. No locking or warning.

Environment

• Claude Code desktop, Windows 11, model Opus 4.8
• Remote Control to the mobile app
• Single local git repository; one working tree, one branch

Expected

• Remote Control mirrors/controls one session, OR
• If two execution contexts exist, both UIs surface that another session is actively

editing this repo, AND concurrent execution on a shared working tree is prevented or
auto-isolated (e.g. separate git worktree).

Actual

• Two sessions executed the same plan concurrently against one working tree.
• Desktop GUI showed nothing about the second session running or editing files.
• The desktop agent had no signal — it only inferred the parallel session after the

fact, from a subagent's git log showing commits it never made, plus harness file-change
notices for files it didn't edit (source files and a shared progress/ledger file changed
underneath it mid-task).

• No lock, no warning, no cross-session activity view.

Impact

Two agents fought over the same files and branch with no coordination. The user could not
see that two sessions were active, and could not tell which one "owned" the work. Easy path
to conflicting commits and lost edits.

Suggested fixes

1. Surface active sibling sessions (especially RC-spawned) in both desktop and web/mobile UIs.
2. Warn or lock when two sessions share a working directory.
3. Clarify/repair whether Remote Control mirrors vs forks a session — a mirror should

not execute independently.

1. Optionally auto-isolate a forked session into its own git worktree.

Related issues

• #28402 — Remote Control session not visible in session list (the visibility half of this bug)
• #68080 — Parallel subagent edits clobber each other; lock is per-agent (the clobbering mechanism, but intra-session)
• #62478 — Duplicate session names when multiple sessions share the same git branch (multi-session / one branch)
• #59818 — /fork command for parallel session branches (forking sessions, as a feature)
• #25434 — nested-Claude launch guard behavior (a guard exists for nested launches; none for RC-forked siblings)

What Should Happen?

Remote control and desktop GUI should let you browse all actively running tasks in the mobile and desktop apps, as well as CLI and web and agents should have visibility

Error Messages/Logs

Steps to Reproduce

Steps to reproduce

1. Start a long-running agent task in a desktop session (here: a multi-task,

subagent-driven implementation plan with per-task git commits).

1. Invoke Remote Control from that desktop session and open it on the phone.
2. Let it run. Observe the phone session executing the task on its own — spawning

subagents, writing source files, and creating git commits — concurrently with the
desktop session.

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.161 (Claude Code)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_