Offshoot

A self-contained, ultra-light version control + review tool for VS Code. No Git. No GitHub. No network. Disk is the source of truth.

Offshoot is a backward snapshot tool. When you open a PR it captures a baseline of whatever you touch; as you edit, it stores only what it takes to walk your changes back. Commit a PR and the baseline is deleted — disk becomes permanent. Revert a PR and disk is restored to the baseline.

Core model

• Disk = truth. Your real files are always "the new". Offshoot never freezes disk or serves a virtual copy.
• A PR is a backward snapshot of only what changed. "The new" is never stored — it's whatever is on disk. Only the old side of touched files is kept.
• Commit deletes a PR's stored baseline (irreversible).
• Revert overwrites disk with a PR's reconstructed baseline.
• Multiple PRs are independent snapshots, keyed by id. They are never reconciled against each other.

Using it

1. Click the Offshoot icon in the Activity Bar.
2. Open PR with a title (and optional notes / custom id).
3. Edit and save files — changes are captured automatically against the baseline. If you start editing with no PR open, Offshoot offers to open one and remembers the original content, so the change that prompted the offer is captured by the PR you open (not lost).
4. Review to paint changes directly in the editor — green for added and blue for modified lines. Removed lines aren't painted in the editor (the text is gone from disk); clicking a changed file opens the custom diff panel to the right, with grouped red/green hunks and per-hunk Commit/Revert actions.
5. Commit to make it permanent, Revert to roll back, or Commit selected to finalize just the lines you've selected. You can also revert a single file from the changes list, and edit a PR's title/notes (✎).
6. While a PR is active, jump between changed regions in the current file with Alt+PageDown / Alt+PageUp (Offshoot: Go to Next/Previous Change).

Offshoot never tracks .offshoot/, .git/, or node_modules/. Add a .offshootignore file at the workspace root (one glob per line) to exclude more.

Storage

Offshoot stores PR data outside the project, under ~/.offshoot/<workspace-hash>. This deterministic location is computed from your workspace path, so the extension and the standalone MCP server both operate on the same PR data. Each open PR is still a self-contained folder (meta.json, deltas.json, cached baseline of touched files); committing a PR deletes its folder and leaves no extra state behind.

Guards

Before any disk-writing operation, Offshoot runs a guard. When a situation has more than one valid fix (overlapping PRs, unsaved buffers, a missing file, a content mismatch), it surfaces a dialog with real action buttons instead of silently refusing. Data-losing choices say so in their label and ask to confirm.

Error reference

When a guard stops an operation, Offshoot shows a modal titled “Offshoot (Error #N): …” with buttons for every genuine fix plus Cancel. Buttons that lose data say so and ask to confirm. Use this table to debug:

#	Meaning	Choices offered
1	Miscellaneous / unspecified failure	Retry · Cancel
2	PR not found (bad id)	Refresh PR list · Cancel
3	Line out of range — stored deltas no longer line up	Re-capture (loses record) · Discard PR · Reveal folder · Cancel
4	Content mismatch — a line changed outside this PR	Keep disk · Force baseline · Re-capture · Cancel
5	PR id already exists	Open existing PR · Use a different id · Cancel
6	No active PR	Open a new PR · Select an existing PR · Cancel
7	PR folder missing / closed	Remove from list · Cancel
8	meta.json unreadable	Reveal folder · Discard PR · Cancel
9	deltas.json unreadable	Re-capture (loses record) · Discard PR · Reveal folder · Cancel
10	Unsaved changes in affected files	Save & continue · Discard & continue · Cancel
11	File no longer exists	Skip this file · Recreate from baseline · Cancel
12	Committing a PR that overlaps other open PR(s) on the same file	Commit this PR only · one Commit button per overlapping PR · Commit all overlapping · Cancel
13	No diff in the selected region	Choose another selection · Cancel
14	A PR title is required (tried to open a PR with no title)	Type a title in the box → Enter to open · Esc to cancel
15	Reverting a PR that overlaps other open PR(s) on the same file	Revert this PR anyway (overwrites to baseline) · Commit an overlapping PR first · Commit all overlapping first · Cancel

Every error offers at least one real action plus Cancel; choosing a fix re-runs the guard before touching disk, so a fix can’t create a new inconsistency.

AI control (MCP)

Offshoot ships a Model Context Protocol server so an AI agent (e.g. Claude Code) can drive PRs — open, inspect, commit, and revert — on the same data the VS Code sidebar shows. The engine is editor-independent, and both the extension and the MCP server compute the same out-of-project storage location for a workspace, so they stay in sync (the sidebar watches that folder and refreshes live).

Register it (defaults to the current working directory as the workspace, so it follows whatever project the session is in):

# portable — runs straight from GitHub, no local path:
claude mcp add offshoot --scope user -- npx -y github:NolanLT/offshoot
# pin a release:        npx -y github:NolanLT/offshoot#v0.1.1
# or run a local build: node "<path-to-offshoot>/dist/mcp/server.cjs"
# pin a workspace:      node "<path-to-offshoot>/dist/mcp/server.cjs" --workspace "C:/path/to/project"
# or set the workspace via env: OFFSHOOT_WORKSPACE="C:/path/to/project"

Tools: offshoot_list_prs, offshoot_open_pr, offshoot_track_files, offshoot_changed_files, offshoot_pr_diff, offshoot_commit, offshoot_revert, offshoot_revert_file, offshoot_recapture.

Headless capture: because baselines are captured from pre-edit content, an AI editing files on its own should call offshoot_track_files for the files it's about to change before editing them; Offshoot then diffs the post-edit disk against that baseline. (When you edit in the VS Code editor, the extension captures baselines automatically — no tracking step needed.)

Files & images

Adding a file of any type during a PR is undone on revert; deleting a file — text or binary (e.g. an image) — restores it byte-for-byte, because Offshoot saves its bytes just before deletion. Binary content changes (editing an image's pixels) are not tracked — only add and delete. Folders work too: deleting a folder restores its whole tree on revert, and reverting an added folder removes it. Deletions are captured when performed through VS Code.

Out of scope (by design)

Merge logic, commit history, branch graphs, stacked/dependent PRs, network, and Git interop. Offshoot is a tight draft/checkpoint-and-review tool, not a full VCS.