timewright

Single-slot undo for Claude's in-session changes — including Bash-driven mutations (deletions, sed/git rewrites) that native /rewind misses.

Version: 1.2.2 · Source · README

Install

/plugin marketplace add Joys-Dawn/toolwright
/plugin install timewright@Joys-Dawn/toolwright

Requires Node.js ≥ 18 and a git repository (timewright uses git worktree add HEAD for snapshotting). Zero config.

Using it

Type /undo to revert Claude's changes from the last turn.

1. Claude runs node bin/undo.js --diff and prints a three-bucket summary:
   • Modified (will be reverted) — restored from snapshot.
   • Added (will be DELETED) — the dangerous set; may include files you created in parallel.
   • Removed (will be restored) — snapshot had them, working tree doesn't.
   • Lists > 20 truncate with "…and N more".
2. If HEAD moved between the snapshot and now (e.g., you ran git reset or git checkout), Claude prints headDrift.snapshot and headDrift.current SHAs and warns.
3. AskUserQuestion asks "Apply this undo?" — Yes, undo or No, cancel.
4. On Yes, Claude runs node bin/undo.js --apply and confirms. If some files couldn't be restored (locked by another process, Windows symlink-privilege, etc.), the exact list is reported.

Coverage

Tool	Covered
Bash	Any command that modifies tracked or untracked source files inside the repo — rm -rf, migrations, git reset, sed/awk rewrites.
Write / Edit	All in-repo file operations.
NotebookEdit	Jupyter notebook changes.

Read/Grep/Glob don't trigger snapshots — they're free.

Files outside the git repo, global package installs, and side effects of Bash commands living outside the repo are not tracked.

Snapshot model

• When: every UserPromptSubmit where a mutating tool fired in the previous turn. Pure Read/Grep/Glob turns skip snapshotting entirely.
• What: every tracked file (git ls-files) plus every dirty or untracked file in the working tree. Includes uncommitted edits.
• Where: .claude/timewright/snapshot/ inside the repo root.
• Single-slot: each new prompt replaces the previous snapshot. /undo rewinds to the most recent snapshot only — no history.

The UserPromptSubmit hook recognizes /undo and /timewright:undo and skips snapshotting on those turns so the existing snapshot stays consumable.

Excluded paths

Combines .gitignore (via git ls-files) with an explicit exclusion set.

• Directories (any path segment matches): .claude, node_modules, .git, dist, build, .next, .nuxt, .output, .turbo, .vercel, .svelte-kit, coverage, __pycache__, .pytest_cache, .mypy_cache, .ruff_cache.
• Secret env files (basename match): .env, .env.local, .env.development.local, .env.test.local, .env.production.local.

.env.example, .env.template, and .env.sample are included — those are routinely committed.

Installed packages aren't snapshot

If Claude runs npm install, undo restores package.json/package-lock.json but not node_modules/. Re-run npm install after undoing a dependency change.

Hooks

Hook	Event	What it does
on-session-start.js	SessionStart	Resolves the git repo root from the launch cwd and records it at <repoRoot>/.claude/timewright/root so later hooks find the project root even if Claude cds into a subdirectory.
on-user-prompt-submit.js	UserPromptSubmit	Clears the stale marker and creates a snapshot. Skips on /undo.
on-post-tool-use.js	PostToolUse on Bash\|Write\|Edit\|NotebookEdit	Flips the stale flag so the next UserPromptSubmit takes a fresh snapshot.

All three hooks fail silently to stderr — they never block a session start, prompt, or tool call.

CLI

bin/undo.js:

Invocation	Behavior
node bin/undo.js --diff	Prints JSON with modified, added, removed, headDrift, counts, hasChanges, snapshotCreatedAt.
node bin/undo.js --apply	Restores the snapshot. Prints JSON with ok, applied, and (partial) errors.

The /undo command invokes both via the Bash tool (not ! preprocessing) so you confirm between --diff and --apply.

State directory

.claude/timewright/ (auto-gitignored):

• snapshot/ — file-tree snapshot
• snapshot.json — timestamp + git HEAD at snapshot time
• stale.d/ — internal flag directory
• root — project-root anchor file