Browser Control Panel

The control panel is available at http://127.0.0.1:8765. FastAPI redirects / to /ui/ and serves the bundled static export directly, so production use does not require a separate Node.js server.

Interface

Arbiter uses a flat, responsive product-console layout with light and dark themes, Radix icons, compact status indicators, and an explicit theme toggle. The sidebar can collapse on desktop and becomes a slide-out menu on smaller screens. Tables remain horizontally scrollable and card layouts collapse as the viewport narrows.

All operations go through the REST API. The browser has no direct Docker or filesystem access, and it cannot bypass Arbiter's approval and verification pipeline.

Navigation

The sidebar groups the application into four areas:

• Workspace: Overview, Stacks, Workspaces, and Topology.
• Runtime: Observability, Containers, Processes, and Ports.
• Manage: Files, Docker resources, Registry, and Ask agent.
• Safety: Approvals, Audit log, Admin, and Settings.

The top bar shows synchronization state, live status, theme controls, refresh, resource search, and a direct Ask Arbiter action. The command palette opens with Cmd+K or Ctrl+K.

Workspace and Runtime

Overview and Workspaces

The overview summarizes listeners, registered projects, containers, approvals, host capacity, recent activity, active stack presets, and quick actions. Workspace views connect registered and runtime-discovered projects with their Compose services and resource evidence.

Multi-Project Stacks & Environment Switcher

The Stacks view (#stacks) manages operational environment profiles:

• Active Stack Banner: Real-time indicator of the running stack preset.
• Stack Presets Grid: Preset cards with project members, tags, and 1-click switcher buttons.
• Boot Order DAG Visualizer: Shows dependency boot stages computed via Kahn's algorithm.
• Readiness Gate Cards: Displays real-time TCP socket, HTTP endpoint, and Docker container health checks with latency metrics.
• Readiness Access Controls: Cards distinguish offline, approval-required, and hard-blocked probes. Operators can request scoped access, review the resulting safety approval, and revoke persisted grants from the stack screen.
• Context Switch Stepper Modal: Provides step-by-step visibility into stopped projects, dynamic .env override injection, port reconciliations, and readiness verification.

Topology

The topology canvas links projects, Compose files and services, containers, images, volumes, networks, ports, host processes, Dockerfiles, and Make targets. It supports zoom and fit controls, project scoping, connected-path focus, local search, and strict natural-language filtering.

Observability

The observability view combines the SSE activity stream with bounded container logs, one-shot metrics, filtering and pause controls, and localhost application previews. Logs and metrics are fetched on demand and are not persisted as authoritative state.

Containers, Processes, and Ports

• Containers show state, health, image, published ports, Compose ownership, bounded logs, and metrics. Lifecycle actions create approval requests.
• Processes show host runtime evidence and listening ports.
• Ports support ownership search, conflict inspection, and deterministic free port suggestions.

Management

Files

The editor is restricted to known configuration files inside explicitly registered projects. Saves show a diff, validate content, require approval when appropriate, create a backup, and support rollback and undo.

Docker Resources

Docker views cover disk usage, images, volumes, and networks. Destructive operations are proposals only; execution remains behind the safety workflow.

Registry

Projects can be registered by explicit path or discovered below configured roots. Each project can be inspected, diagnosed, prepared for conflicts, started, stopped, restarted, or unregistered without deleting its files.

Ask Agent

Agent responses stream as GitHub-flavored Markdown alongside typed execution events for routing, model phases, tool calls, redacted arguments, evidence, and errors. The trace never exposes private model chain-of-thought. Any proposed mutation still becomes a separate approval.

Safety and Administration

Approvals and Audit Log

Pending approvals show the exact action, immutable arguments, risk level, summary, visual side-by-side diffs (with automatic secret masking), simulated runtime state transitions (time-travel previews), and expiration. Operators can reject a request or approve and execute the stored payload. The audit log keeps action and verification outcomes separate so an operation is never presented as successful when verification failed.

Admin and Settings

Admin surfaces rolling API latency, LLM usage, event-pipeline state, process/database health, the agent harness, and safety policy. Settings explains the active local configuration and the boundaries around remote exposure.