/herdr

name: herdr
description: "Control Herdr, a terminal multiplexer for coding agents. Use only when the user explicitly mentions Herdr or asks to use Herdr to inspect or control panes, tabs, workspaces, commands, or another agent. Do not use merely because a task could benefit from a background terminal, delegation, or parallel work. Requires HERDR_ENV=1."

Herdr

Herdr organizes terminals into workspaces, tabs, and panes, recognizes coding agents running inside panes, and exposes the current session through the `herdr` CLI.

Before issuing any control command, verify that this agent is running inside a Herdr-managed pane:

test "${HERDR_ENV:-}" = 1

If the check fails, say that you are not running inside Herdr and stop. Do not inspect or control the focused Herdr session from outside Herdr.

When the check passes, the `herdr` binary in `PATH` talks to the current session. Use it to inspect neighboring work, create terminal layout, start agents and commands, read output, and wait for state changes.

Learn the current CLI

The installed binary is the authority for command syntax. Start with:

herdr --help

Then print the relevant command group by running the group without a subcommand:

herdr agent
herdr pane
herdr workspace
herdr tab
herdr worktree
herdr terminal
herdr notification
herdr integration
herdr session
herdr machine

Do not run bare `herdr` for discovery; it launches or attaches the TUI. Do not probe a mutating nested command by omitting arguments. Commands such as `herdr workspace create` are valid with defaults and will execute.

Most control commands return JSON. Read identifiers and state from those responses instead of predicting them.

Understand layout, panes, and agents

Choose the primitive that matches the job:

• Workspace, tab, and pane topology organize terminal locations.
• Pane commands control raw terminals, shells, tests, servers, input, and output.
• Agent commands control the recognized coding agent currently occupying a pane.

A pane exists whether or not it contains an agent. `agent start` requires an existing available shell pane and never creates, splits, or moves layout. Use pane commands for ordinary processes. Use agent commands when Herdr must validate agent identity or interpret `idle`, `working`, `blocked`, `done`, and `unknown` lifecycle states.

Agent commands accept either a unique live agent name or the pane ID currently hosting that agent. They do not accept terminal IDs or bare agent-kind labels. Names must match `[a-z][a-z0-9_-]{0,31}` and be unique among live agents. A name follows the current pane occupant and is cleared when that agent exits, is released, or is replaced. Suspending an agent with Ctrl+Z and running a non-agent command preserves its identity while the exact process remains alive. This does not preserve the original identity across another recognized agent taking over. A retained identity does not mean the agent is in the foreground; inspect the pane before sending input.

`idle` and `done` normally indicate the agent is ready for input; neither guarantees that an unfamiliar approval dialog was recognized or that a retained agent is in the foreground. The CLI/API uses the server's seen state to distinguish them; explicit focus commands mark the target seen, while reads do not. Each TUI client tracks viewed completions independently, so its Done badge can differ from the CLI or another client's badge. Antigravity and Grok can be idle while background tasks or subagents keep running, so a settled-state wait is not proof those jobs have finished. `blocked` means Herdr recognized an approval or question UI. `unknown` means an agent is present but Herdr cannot classify it confidently; it does not prove completion.

Use IDs and caller context

Public IDs are opaque stable handles:

• workspace: `w1`
• tab: `w1:t1`
• pane: `w1:p1`

Closed tab and pane IDs are not reused. A pane moved into another workspace receives a new workspace-qualified pane ID. After `pane move`, continue with `.result.move_result.pane.pane_id` or the live agent name. The old value is reported as `.result.move_result.previous_pane_id`; only the moved process's inherited caller context keeps resolving that old ID, so do not use it as a general agent target.

Herdr injects the caller's context into each managed pane:

printf '%s\n' "$HERDR_WORKSPACE_ID" "$HERDR_TAB_ID" "$HERDR_PANE_ID"

Prefer `--current` when a pane command should target the calling pane. An omitted `pane split` target uses the calling pane when `HERDR_PANE_ID` is available, otherwise the focused pane. Other commands may use the UI-focused pane, which can belong to the user or another client.

Discover live state with:

herdr workspace list
herdr tab list --workspace "$HERDR_WORKSPACE_ID"
herdr pane current --current
herdr pane list --workspace "$HERDR_WORKSPACE_ID"
herdr agent list

Creation responses expose the IDs to use next. `workspace create` returns `.result.workspace`, `.result.tab`, and `.result.root_pane`. `tab create` returns `.result.tab` and `.result.root_pane`. `pane split` returns the new pane as `.result.pane`.

IDs and live agent names are scoped to one server. Two saved SSH machines can both have `w1:p1` or an agent named `reviewer`. Selecting a machine in the TUI does not retarget commands running in your pane: without `--machine`, they still use the inherited session and socket context.

To control a saved SSH machine, use the same global prefix for discovery and every later command:

herdr --machine <label-or-id> agent list
herdr --machine <label-or-id> pane list
herdr --machine <label-or-id> agent prompt <remote-agent-name> "Reply with your current status." --wait --timeout 120000

The selector must be an enabled saved profile ID or a unique, case-sensitive label, not an arbitrary SSH hostname. Commands use that profile's remote session without an open TUI. Do not combine `--machine` wi