Fix cavemem hooks failing with "Executable not found in $PATH: sh"

runbook Mon Jun 29 2026 00:00:00 GMT+0000 (Coordinated Universal Time) cavememclaude-codehookswindowspathtroubleshooting

Fix cavemem hooks failing with "sh not found"

Symptom

In Claude Code, at the end of any turn:

● Ran N stop hooks (ctrl+o to expand)
  ⎿  Stop hook error: Failed with non-blocking status code:
     Error occurred while executing hook command:
     Executable not found in $PATH: "sh"

Same error fires for SessionStart, UserPromptSubmit, PostToolUse, SessionEnd if you check the logs. Hooks are silently non-blocking, so nothing breaks — but cavemem records nothing, semantic search results stay stale, and you waste a subprocess spawn every event.

Root cause

Claude Code wraps every type: "command" hook in sh -c <command> before executing. On Windows without C:\Program Files\Git\bin (or another POSIX shell directory) on PATH, sh.exe isn't resolvable from CC's process tree, the wrapper dies, and the inner command never runs.

The native Bash tool inside CC can still see /usr/bin/sh because Git Bash sets up its own internal PATH — but that doesn't help hooks, which CC spawns from its parent process whose PATH is the user-environment PATH from [Environment]::GetEnvironmentVariable('Path','User').

This machine had C:\Program Files\Git\cmd (contains git.exe but no shells) on user PATH but NOT C:\Program Files\Git\bin (contains sh.exe, bash.exe, all POSIX shims).

Fix

Add C:\Program Files\Git\bin to user PATH (not system — single-user change):

powershell -NoProfile -Command "
  $current = [Environment]::GetEnvironmentVariable('Path','User')
  $add = 'C:\Program Files\Git\bin'
  if ($current -notlike \"*$add*\") {
    [Environment]::SetEnvironmentVariable('Path', $current + ';' + $add, 'User')
    Write-Output 'PATH updated'
  } else {
    Write-Output 'already there'
  }
"

Persistent across reboots. Restart Claude Code to inherit the new PATH (existing CC processes retain the old one).

Verify

where.exe sh      # should resolve to C:\Program Files\Git\usr\bin\sh.exe

Then in a fresh CC session, run any tool call and check Stop hook indicator returns ok not error.

In cavemem itself:

cavemem status   # observation count should grow turn-over-turn
cavemem search "anything" --limit 3   # should return scored results

Related fix — semantic search dead

If cavemem search returns semantic disabled: Local embedding provider requires @xenova/transformers, the peer dep is missing. Install:

npm install -g @xenova/transformers

~80 packages, ~100MB. FTS search keeps working without it; only vector-similarity recall is gated.

Anti-patterns

❌ Edit ~/.claude/settings.json env.PATH instead — CC reads its own settings AFTER spawning the hook subprocess wrapper, so env block doesn't help here
❌ Add C:\Program Files\Git\usr\bin instead of \bin — both contain sh.exe but \bin is the documented entry-point + has the right Windows symlink shims
❌ Set system PATH instead of user PATH — needs admin, no benefit for single-user machine, harder to roll back
❌ Try to make CC NOT wrap hooks in sh -c — not a setting, hard-coded harness behavior

Why this rule lives here

Documented after hitting the bug on 2026-06-29. cavemem memory search showed memories from a prior session that mentioned "cavemem's Claude Code hooks are still wired, so it auto-restarts on next session" — meaning we'd hit and silently lived with the same problem at least once before. Captured as runbook so we don't pay the discovery cost a third time.

Cross-refs

services/infra/dev-tools/cavemem — what cavemem is and how it's wired