Overview
This skill manages persistent terminal sessions via tmux. Two modes:
| Sandbox Mode | Host Mode | |
|---|---|---|
| Where tmux runs | In the assistant's sandbox | On the user's host machine |
| How user connects | vellum terminal attach <session-name> |
User opens their own terminal |
| Assistant access | Direct (bash tool) |
Via host_bash |
| Best for | Long-running builds, servers, always-on tasks | Work needing host access (e.g. SwiftUI builds, host-local services) |
Default: Use Sandbox Mode unless the task specifically requires host access. Details: sandbox-sessions.md · host-sessions.md · tmux-best-practices.md
Prerequisites
Sandbox Mode: No setup needed — tmux is available in the sandbox.
Host Mode: Requires tmux on the host — see host-sessions.md.
Workflow: Orchestrating Multiple Sessions
- List all sessions:
tmux list-sessionsto get names and current commands - Read each:
tmux capture-pane -t NAME -p -S -50(30-50 lines is usually enough) - Summarize before acting: "Build done, tests at 73%, deploy waiting for confirmation"
- Act on the user's instructions