Wan Huiyan Agent Traffic Control Main Bash Cwd Persists Nested Worktree

Main-agent Bash cwd persistence → nested worktrees at wrong path

Problem

You're orchestrating multiple parallel-dispatch subagents, each in its own git worktree. From the main agent's Bash tool you do:

git worktree add .claude/worktrees/track-A origin/main -b feat/track-A
# ... dispatch Track A subagent ...
# ... investigate codebase ...
cd /path/to/repo/.claude/worktrees/track-A && grep -rn "foo" src/   # persists cwd!
# ... time passes, you dispatch Track B ...
git worktree add .claude/worktrees/track-B origin/main -b feat/track-B

You expect track-B at <repo>/.claude/worktrees/track-B. Instead git worktree list reports it at <repo>/.claude/worktrees/track-A/.claude/worktrees/track-B — nested inside the Track A worktree.

Branches, commits, and pushes still work (git resolves them via .git/worktrees/<name> metadata regardless of disk location), but:

• Dispatched subagents pointed at the intended path will report "worktree path mismatch."
• Cleanup (git worktree remove .claude/worktrees/track-B) from the project root won't find it.
• Per-worktree caches, venvs, and uploads end up under the wrong parent directory.

Context / Trigger conditions

• Main agent runs more than one git worktree add in the same session.
• Between worktree-add calls, the main agent ran a Bash command that included a cd to a path other than the project root.
• The later git worktree add uses a relative path (e.g., .claude/worktrees/<name>).
• Symptom: git worktree list shows nested paths, OR a subagent given the intended path can't find its worktree, OR pwd inside a subagent reports a longer-than-expected path.

The Bash tool's own description says it: "The working directory persists between commands, but shell state does not." This is the opposite of subagent Bash, which resets cwd per call (see subagent-bash-cd-wrong-worktree).

Solution

Three reliable mitigations, in order of preference:

1. Always pass an absolute path to git worktree add from the main agent.

   git worktree add /Users/huiyanwan/Documents/AMC-handover/.claude/worktrees/track-B origin/main -b feat/track-B
   

   This is the cleanest fix and is robust against any cwd drift.

2. Reset cwd to project root in the same chained call before any git worktree add with a relative path:

   cd /Users/huiyanwan/Documents/AMC-handover && git worktree add .claude/worktrees/track-B origin/main -b feat/track-B
   

3. Create ALL worktrees up-front in a single batch at the start of the session, before any other Bash commands that might cd.

When dispatching parallel subagent prompts, also bake an absolute-path verification step into each prompt:

First action: verify worktree path matches expectation.
cd /Users/huiyanwan/Documents/AMC-handover/.claude/worktrees/<name>
pwd  # MUST end in <name>; STOP and report if it doesn't
git rev-parse --abbrev-ref HEAD  # MUST be feat/<name>

Verification

After creating a worktree, immediately:

git worktree list | grep <name>

The reported path must NOT be nested under another worktree. If it is, before any subagent dispatch:

# Move it to the correct location (requires admin; or just remove + re-add)
git worktree remove <wrong-nested-path>
git worktree add /abs/path/to/.claude/worktrees/<name> origin/main -b feat/<name>

Example

What went wrong (Session 15, AMC-handover):

# Main agent at /Users/huiyanwan/Documents/AMC-handover (project root)
git worktree add .claude/worktrees/s15-lows-bundle origin/main -b feat/s15-lows-bundle
# → created at .../AMC-handover/.claude/worktrees/s15-lows-bundle ✅

# Later, investigation:
cd /Users/huiyanwan/Documents/AMC-handover/.claude/worktrees/s15-lows-bundle && grep "_JINJA_ENV" src/
# → main shell cwd is now inside s15-lows-bundle worktree

# Even later, second worktree:
git worktree add .claude/worktrees/s15-csv-upload origin/main -b feat/s15-csv-upload
# → created at .../s15-lows-bundle/.claude/worktrees/s15-csv-upload ❌

Fix applied in that session: none mid-session (PRs all pushed correctly via branch refs). The lesson is to use absolute paths next time.

Notes

• Branch and push behavior are NOT affected because git tracks worktrees by .git/worktrees/<name> metadata, not by filesystem path. So this bug is silent — you only notice when a subagent reports a path mismatch or when you try to git worktree remove from the project root.
• This is a property of the Claude Code Bash tool specifically. Other tools (e.g., Edit, Write, Read) don't have a persistent cwd — they take absolute paths or resolve against the project root.
• The subagent variant (subagent-bash-cd-wrong-worktree) describes the opposite failure mode: subagent shells reset cwd per call, so a cd followed by git commit in a separate Bash call commits to the parent repo's HEAD. Both are real, and the fix is the same: use absolute paths and verify with pwd before any state-changing command.

References

• Claude Code Bash tool docstring: "The working directory persists between commands, but shell state does not."
• Related skill: subagent-bash-cd-wrong-worktree — the inverse failure mode in subagent shells.
• Related skill: using-git-worktrees — general worktree workflow.

Source: wan-huiyan/agent-traffic-control — distributed by TomeVault.