what a recovery point holds, /rewind, the editor's Undo, and what cannot come back

Every turn DGC runs itself opens a recovery point. /rewind takes the code and the conversation back to one of them.

• One per turn, before the model sees your message. A standing goal that runs several work cycles from one prompt opens one per cycle. A follow-up typed while a turn is running joins that turn and does not open one of its own.
• Sub-agents do not open their own. Their edits are captured into the parent turn's point — as they happen in a shared checkout, or when an isolated worktree is integrated. /tasks apply opens a point of its own.
• Turns delegated to a subscription CLI open none. Claude Code, Codex, Qwen, Kimi and Copilot edit files outside DGC's file tools, so there is nothing for DGC to snapshot.
• If the point cannot be saved, the turn does not start. DGC refuses the prompt rather than run a turn it could not take back.

• The exact conversation up to just before that prompt — not a summary, and not a message count that compaction can shift.
• Each file's pre-edit state, taken the first time the turn's file tools (write_file, edit_file, multi_edit, apply_patch) touch it: the exact bytes, the permission bits, a symlink's target, or the fact that the file did not exist yet.
• Capture comes first. The snapshot is saved to the session before the tool runs. If it cannot be — the file changed while being read, the snapshot budget is spent, the turn has already captured 4,096 files, the path is not a regular file, or the session could not be re-saved — the edit is refused and the file is untouched.

/rewind lists every point, oldest first: the opening 70 characters of the prompt as DGC received it (a point opened by /tasks apply reads apply retained task ID) and how many files it captured. Pick one and confirm — Reverts N file(s) and truncates the conversation. This cannot be undone. Files touched at that turn or any later one return to their earliest saved state (a file the turn created is deleted; any new directories it was created in are left behind), the conversation returns to just before that prompt, and that point and every later one are consumed. If any step fails, the files and the point are rolled back and kept.

It always restores both — there is no code-only or conversation-only rewind, and no redo. It is refused while a turn is running: stop the turn (Esc) or let it finish, then run /rewind again. dgc --classic skips the confirmation. The standing goal, the todos and Context Notes stay as they were.

Undo, on the files-changed card under an answer that edited files, finds the recovery point by the prompt that opened it, asks once, and performs the same rewind. A turn that changed no files shows no card — use /rewind. If no remaining point was opened by that prompt, Undo declines rather than guess; if the same prompt opened more than one point, it takes the most recent one — /rewind lets you pick another. /rewind in the editor lists every point and rewinds as soon as you pick one.

/branch (/fork) is the non-destructive alternative: a new chat that carries the conversation, the standing goal, the todos and the recovery points, while the chat you came from stays as it stands (its /recall archive of compacted turns stays with it). Nothing is reverted. The editor offers it under a finished answer.

• Shell writes. bash, the Python code-action, MCP tools, save_memory (your project's DGC.md) and add_skill are never snapshotted. A file a shell command changed comes back only to the state a file tool later found it in: if a file tool snapshotted it before the shell ran, the shell's change is undone; if the shell ran first, that change stays.
• Files outside the project. An approved external path is rewindable in the current process only; its snapshot is never saved with the session.
• A moved project. Points are bound to the directory they were saved from and do not load after a move or rename — and the first prompt in the moved directory saves over them, so they are gone for good. Move the project back before resuming if you need them.

Points are saved inside the session itself, re-saved the moment a point opens and the moment a file is first captured, so they survive /resume and context compaction. There is no time limit: the newest 512 points are kept, up to 4,096 files each, within 128 MB of snapshots in total. Redaction rewrites the conversation each point holds; file snapshots stay byte-for-byte as captured, because they are the rollback data.