Summary

The auto-deployed context-mode-cache-heal.mjs SessionStart hook fails to launch on Windows when Claude Code uses Git Bash and the project working directory is on a drive other than C:. MSYS path translation rewrites the script path, and node cannot find the module.

Environment

• OS: Windows 11 Pro (10.0.26200)
• Shell used by Claude Code on Windows: Git Bash (MSYS)
• Node: v24.8.0
• context-mode: 1.0.100 (npm + plugin both installed)
• Project cwd at session start: D:\Data\postit-extractor (non-C: drive)

Symptom

On every session start:

SessionStart:startup hook error
Failed with non-blocking status code: node:internal/modules/cjs/loader:1423
  throw err;
  ^
Error: Cannot find module 'D:\c\Users\shaun\.claude\hooks\context-mode-cache-heal.mjs'

Note the mangled path D:\c\Users\shaun\... — MSYS prepended the cwd's drive letter (D:) to a /c/Users/...-style path it tried to translate.

Hook command (deployed in ~/.claude/settings.json)

{
  "type": "command",
  "command": "node C:\Users\shaun\.claude\hooks\context-mode-cache-heal.mjs"
}

Root cause

When Claude Code on Windows runs the hook through Git Bash, the JSON-decoded path C:\Users\shaun\... is processed in a way that triggers MSYS path translation. With cwd on D:\, MSYS converts a /c/Users/...-style intermediate form back into D:\c\Users\... — a non-existent path.

Reproduction (cwd on D:):

$ bash -c 'node ~/.claude/hooks/context-mode-cache-heal.mjs'
Error: Cannot find module 'D:\c\Users\shaun\.claude\hooks\context-mode-cache-heal.mjs'

$ bash -c 'node "$HOME/.claude/hooks/context-mode-cache-heal.mjs"'
Error: Cannot find module 'D:\c\Users\shaun\.claude\hooks\context-mode-cache-heal.mjs'

$ bash -c 'node "$USERPROFILE/.claude/hooks/context-mode-cache-heal.mjs"'   # exit 0

$USERPROFILE resolves to a native Windows path (C:\Users\shaun) and bypasses MSYS conversion.

Fix

Change the deployed hook command to use $USERPROFILE (or another platform-aware form) on Windows:

"command": "node \"$USERPROFILE/.claude/hooks/context-mode-cache-heal.mjs\""

Verified: works regardless of which drive the project cwd is on.

Other options that also work:

• Use cmd /c wrapper to avoid bash entirely on Windows
• Inline the script with node -e so no path is needed
• Detect platform during deploy and emit the appropriate path form

Impact

Anyone on Windows who opens a Claude Code session with a project on a non-C: drive sees a hook error every session-start. The cache-heal logic itself never runs, so the underlying claude-code#46915 workaround silently does nothing for these users.

Workaround for affected users

Manually edit ~/.claude/settings.json and replace the SessionStart hook command with:

"command": "node \"$USERPROFILE/.claude/hooks/context-mode-cache-heal.mjs\""