Sessions & workspaces

Everything you see in C3 Mobile mirrors Herdr's model on your machines. Knowing the hierarchy makes the app immediately legible:

text

Host (one bridge per machine)
└── Session (a named Herdr instance)
    └── Workspace (a project context, rooted at a directory)
        └── Tab
            └── Pane (a terminal — possibly with an agent attached)

Host — a machine running C3 Bridge. Identified by the --host-id you chose at bridge setup.
Session — one running Herdr instance. Most machines run one; named sessions appear separately.
Workspace — Herdr's unit of project context, anchored to a working directory. When you create one from the phone you provide that directory (an absolute path on the host) and an optional label.
Tab / pane — exactly the terminal layout you'd see at the desk. Panes can be split and closed from the Workspace tab.
Agent — a coding agent (Claude Code, Codex, …) attached to a pane. Agents are what the Signal screen tracks and the session cockpit controls.

Live state, not a mirror

The app renders a snapshot of this topology and keeps it fresh from bridge events. Pull-to-refresh (or reopening a screen) requests a new snapshot. Snapshots are bounded — very large hosts are capped at 256 sessions per snapshot — and transfer as encrypted chunks.

Because state lives on the host, nothing is "in" the phone: closing the app loses nothing, and two phones paired to the same bridge see the same topology.

Host capabilities

Not every host supports every operation, and the app grays out what a host can't do. A bridge advertises per-host capabilities, including:

Terminal mode — live streaming on Linux/macOS; snapshot-refresh mode on Windows.
Lifecycle operations — which workspace/tab/pane create-close operations Herdr's version exposes.
Notifications — whether the bridge delivers push for this host.

What stays on the desk (for now)

Current beta boundaries, so you're not hunting for features that aren't there:

Starting new agents happens in Herdr on the host; the phone controls agents that are already running.
Renaming workspaces, tabs, panes, or agents isn't exposed in the app yet.
Some workspace lifecycle nuances (split direction/ratio, focus control) follow later.

The protocol already carries most of these, so they arrive as app updates, not new infrastructure.