Features

AI, integrations, real-time sync, desktop, and cross-platform capabilities

Cross-cutting capabilities that span the whole platform. For how these pieces connect, see Architecture.

Real-time sync

Start.chat syncs in real time across all your devices. Messages appear instantly, edits propagate immediately, and the UI updates optimistically before the server confirms — so everything feels fast even on slow connections.

The sync engine is offline-first. If you lose connectivity, you can keep reading and composing. When you reconnect, everything syncs automatically with conflict resolution handling simultaneous edits.

AI

A built-in AI assistant called HUD is available in every server. You can interact with it in three ways: mention @hud in any message for an inline response, use the dedicated HUD channel for longer conversations, or open the HUD sidebar for a private chat that doesn’t appear in channels.

Model tiers

HUD uses different model tiers based on task complexity. Server admins set the default tier, and HUD automatically selects models within that tier:

Per-channel AI profiles

Each channel can have its own AI configuration with a custom model tier, system prompt, and ability toggles. This means the same HUD agent can behave differently in your #support channel (friendly, focused on docs) versus your #engineering channel (technical, with code abilities enabled).

Multiple agents per channel

Channels aren’t limited to HUD. You can add multiple AI agents to a single channel, each with its own response mode — one agent for code review, another for customer lookup, a third for task management. External agents connect via webhook or websocket, and tools like OpenClaw work as drop-in agents. Each agent responds independently based on its configured trigger (all messages, threads only, mentions only, etc.).

AI abilities

HUD has access to a set of abilities that can be enabled or disabled per server or per channel:

HUD understands conversation context including recent messages, available apps, your role, and the current channel’s configuration.

Integrations

Connect external services to bring your tools into one place. Built-in apps are available for common services:

Install integrations from Server Settings → Apps. Most connect through OAuth with one click. Integrations receive real-time events via webhooks with signature verification.

You can also create blocks — inline UI that renders right in chat. Write them in a conversation, have HUD generate one, or develop them locally on desktop. Blocks are perfect for dashboards, visualizations, and lightweight internal tools.

Cross-platform

A single codebase powers all platforms:

The same features work everywhere — channels, threads, apps, AI, search, and notifications are consistent across web, desktop, and mobile.

Desktop

The native desktop app adds features that take advantage of running locally.

Local workspace sync

Desktop sync mirrors your server’s apps and workflows to your filesystem at ~/start/{server-slug}/. Edit app code in your favorite editor, and changes push back to the server as drafts. Cloud edits automatically write to your local files too.

Safety features protect against accidental changes: mass change detection, large change ratio checks, freshness verification, and per-file confirmation. Enable sync in Server Settings → Sync.

Native features

The desktop app supports deep links (start-chat://) for OAuth flows and quick navigation, background auto-updates with restart prompts, native notifications, and window state persistence across sessions.

Custom domains

Access your server at your own domain instead of start.chat. Point a CNAME at start.chat, verify DNS in Server Settings, and you’re live. Authentication works seamlessly across domains — members log in the same way regardless of which URL they use. See Servers for setup instructions.

Meetings

Built-in video and audio meetings with screen sharing, accessible from any channel. Meetings run on Cloudflare’s infrastructure for low-latency connections.

Keyboard shortcuts

Full keyboard shortcut support with a discoverable help menu (⌘/). Navigate channels, compose messages, and manage threads without touching the mouse.

Messages also have single-key shortcuts (P, E, R, T, D) that work when hovering.