Glossary

spwn uses one word per concept. If two words seem to mean the same thing, this page is the tiebreaker — the UI, tooltips, and these docs all follow it.

Project

A name plus a working directory. A project groups your sessions and shells. spwn owns projects itself (it doesn’t derive them from Claude’s folders).

Session

An isolated Claude workspace: its own conversation and its own copy of your code. Each session runs on its own git branch in its own worktree (a separate checkout on disk), so parallel sessions never clobber each other. Switching between sessions is a pure focus change — nothing is copied in or out of your main checkout.

The whole point: explore many sessions cheaply, then merge the ones that worked.

Shell

A plain terminal inside a project. No conversation, no worktree — just a shell in the project directory.

Fork (verb)

To fork is to start a new session from a point in an existing one. The new session carries the parent’s conversation history and branches its code, then goes its own way. “Fork” is the only word spwn uses for branching a conversation — so that “branch” can mean exactly one thing:

branch (noun)

The git branch a session’s worktree lives on (spwn names them spwn/<id>). It’s a property of a session — shown as a ⎇ chip — never an action you take. To create a new line of work you fork a session; the git branch comes with it.

Merge tray

A per-project space (▦) where you collect reusable blocks — notes, files, and individual turns picked from any session — and then Inject them as the first message of a fresh session. It’s how you bring the good parts of several explorations back together. (Formerly called “Context”; renamed so it isn’t confused with the model’s context window.)

Inject

The action on the Merge tray — Inject → new session — that assembles the tray’s blocks into a first message and opens a new session seeded with it. To add a turn to the tray from a conversation, use ＋ ctx on that message.

Merge

Bringing a session’s committed work back into its base branch with ordinary git. The session’s worktree branch (spwn/<id>) merges into the branch it was forked from.

Checkpoint / Timeline

A checkpoint is a copy-on-write snapshot of a session’s files, captured after each turn. The Timeline (a tab in a session’s Inspector) is the single place you return to an earlier point — the ↺ Return here action lets you roll back the conversation, the files, or both.

Scheduled task

A read-only task Claude runs against a project on a daily or weekly schedule (◷), optionally reusing the project’s Merge tray. The result arrives as a new session flagged for your attention.