The New dialog

The New dialog starts a coding agent in a fresh herdr pane, or opens a plain terminal, on any host lasso can reach. Open it with the footer's New button, ⌘O (Git agent), ⌘⇧O (Scratch agent) or ⌘I (terminal form), or the input dial's New target on a phone.

It has two tabs, Agent and Terminal. From the chat view or the Grid only the agent form is offered, titled New agent, since those views have no terminal to show a new shell in. ⌘↩ (or Ctrl↩) submits either form from any field.

Choosing the host#

The host picker sits at the bottom of the dialog, beside the create button. A host that is unreachable, not running herdr, or running an incompatible herdr is listed as unavailable and cannot be picked. When the dialog opens, the host is chosen in this order:

1. the host pinned in Settings → General → Agents → New agent/terminal host;
2. the host you last left the picker on in this browser;
3. the host you last created something on;
4. the host this browser tab is on.

If that host has since become unusable, the dialog falls back to this tab's host. After a successful create, lasso moves this browser tab to that host and focuses the new pane.

The Agent form#

Git or Scratch#

The first choice is the kind of agent:

• Git creates a new git worktree and branch off a repository, and runs the agent in it. lasso uses herdr's worktree support, so the worktree appears in herdr under its repository's workspace.
• Scratch creates a fresh empty directory under ~/.lasso/scratch/ and opens the agent as a new tab in the host's shared Scratch workspace. Use it for work that is not tied to a repository.

Fields#

The levels offered for Thinking effort:

Advanced#

The Advanced button reveals more fields. Whether it is open is remembered.

Remembered between openings#

The dialog remembers, per host and in this browser, what you last selected: Git or Scratch (unless it was opened with ⌘O or ⌘⇧O, which pick one), the repository, the agent, and that agent's model, effort, extra args, plan mode and advisor settings, plus the branch prefix and whether Advanced is open. Model, effort and the other harness-specific values are only restored for the same harness. The prompt and attachments are never kept.

What happens when you create#

Create agent returns as soon as the worktree (or scratch directory), the herdr pane and lasso's record of the agent exist. The rest happens in the background in that pane:

1. For a Git agent, the repository's Copy files into worktree globs are copied from the repository into the new worktree.
2. Attachments are moved into the working directory.
3. The setup commands run in the pane's shell: the repository's Setup commands for a Git agent, the host's Scratch setup commands for a Scratch agent.
4. The agent's CLI is launched with your prompt, model, effort and flags. A long or multi-line prompt is staged in a file and read by the launch command, so it is never typed into the shell.

Git worktrees are created under ~/.lasso/worktrees/<repository>/ on the agent's host. If a create is interrupted (lasso restarting during an update, a dropped connection), the dialog retries automatically, and a resubmitted create for the same branch resumes the interrupted attempt rather than making a second worktree.

With Auto-title new agents on (the default), lasso then asks a local agent CLI to summarise the whole prompt into a short title, which renames the herdr workspace, and a one- or two-word name, which becomes the agent's herdr label (and a scratch agent's tab). The branch and directory keep the names derived from the prompt's first line. See Settings.

Agents can also be created by other agents through the create_agent MCP tool, which takes the same choices. See MCP tools and Agents.

The Terminal form#

The Terminal tab opens a plain shell, optionally running a command, as a new herdr tab.

Create terminal opens the tab, focuses it, and moves this browser tab to the selected host if needed. If the command or the tab name could not be applied, the terminal is still created and a notice says what went wrong.

Settings that shape the dialog#

These live in Settings → General → Agents. The Configuring host picker chooses which host you are editing; each host stores its own values in its own ~/.lasso/lasso.db. Changes save automatically.

New Agent defaults

New terminal defaults

Per-repository setup

Pick a Repository, then set:

Both apply to every agent created from that repository, whoever creates it.