Key Concepts

Channels

A channel is how you talk to your assistant. Your assistant is the same everywhere — same personality, same memories, same skills. The only thing that changes is where you're talking to it and what the channel can do.

Web

The browser experience. Sign in at your Vellum Cloud URL and you're talking to your assistant in seconds, no install required. Works on any modern browser, any device.

• Chat — full conversational UI with cards, tables, forms, and other rich surfaces
• About your assistant — browse identity, skills, workspace files, contacts, and memories
• Document editor — long-form writing with your assistant as collaborator
• App viewer — interactive apps your assistant builds render right in the page
• Voice input — press to talk using your browser's microphone
• Approvals — native in-page permission prompts, same as the desktop app

Web is cloud-only by design — the assistant runs in your Vellum Cloud account, with the workspace and sandbox living there. The browser doesn't have access to your local machine, so host file access, shell commands, computer use, and screen watch aren't available here. For those, use the desktop app.

Desktop App

The desktop experience is available on macOS and Windows, with a menu bar presence on Mac and a system tray icon on Windows:

• Chat — type messages, see responses, interact with cards, tables, and other UI surfaces
• Computer use — your assistant can see your screen and control your Mac or Windows PC directly
• Voice input: use the in-app voice controls or configure your voice shortcut in Settings
• Document editor — long-form writing with your assistant as collaborator
• App viewer — interactive apps your assistant builds render right in the window
• Screen watch — your assistant can observe what you're doing and offer context-aware help
• Host file & shell access — your assistant can read files and run commands on your machine

Some features depend on the operating system. The Fn voice key and floating companion are macOS-only. Windows uses a configurable voice mode shortcut and supports computer control in normal, non-elevated windows.

iOS

The pocket experience. The Vellum Assistant app on iPhone and iPad signs into your Vellum Cloud account and gives you the same assistant you talk to on the web and desktop, with the same memory and the same conversations carried across.

• Chat anywhere — full conversational UI on the go
• Conversation continuity — pick up where you left off on Mac or web; history is shared
• Push notifications — your assistant can reach you when something needs your attention
• Approvals — native iOS prompts when a tool call needs your go-ahead

Like Web, iOS is cloud-only by design. The assistant runs in your Vellum Cloud account, so host file access, shell commands, computer use, and screen watch live with the desktop app.

Android

The Android app is the same kind of pocket client as iOS: it signs into your Vellum Cloud account and carries the same assistant, memory, and conversations.

CLI

A command-line interface for interacting with your assistant from the terminal. Uses the same SSE streaming connection as the desktop app — meaning it's a full interactive interface, not just a dumb pipe.

Permission approval prompts work natively in the CLI, and all sandbox-based skills are available. Useful for scripting, automation, or if you prefer working in a terminal.

Telegram

Connect a Telegram bot to your assistant and message it from anywhere. Setup takes a few minutes:

1. Create a bot via BotFather
2. Give your assistant the bot token
3. Your assistant registers the webhook automatically

From there, you can chat with your assistant in Telegram like any other contact. It supports text, images, documents, and interactive inline buttons for approvals. When your assistant needs permission to do something, it sends an inline keyboard you can tap.

Telegram currently works in private chats only. Messages and button taps from groups, supergroups, and channels are not supported yet.

Slack

Connect your assistant to Slack workspaces via Socket Mode. It can:

• Respond to @mentions in channels
• Hold threaded conversations
• Send rich messages with Block Kit formatting
• Handle approvals via interactive buttons
• Send ephemeral messages (visible only to you) for sensitive prompts

Slack has a unique feature: per-channel permission profiles. You can configure which tool categories are allowed in which Slack channels, block specific tools, and set trust level overrides.

Email

Email works in two distinct modes: managing your email and giving the assistant its own inbox.

Your email (Gmail)

Connect your Gmail account via Google OAuth and your assistant becomes a full email manager.

• Read, search, and triage your inbox
• Draft and send emails on your behalf (draft-first workflow — nothing sends without your approval)
• Archive, label, trash, and organize messages
• Unsubscribe from mailing lists
• Bulk declutter with sender digest scanning
• Create inbox filters for automation
• Manage attachments, forwarding, and follow-up tracking
• Vacation auto-responder

Gmail is also a platform in the unified messaging system — your assistant can read, search, and send across Gmail, Telegram, and other connected platforms through a single interface.

Assistant's own email (AgentMail)

Your assistant can also have its own email address. This is behind a feature flag (email-channel) and uses a provider-agnostic architecture — currently backed by AgentMail.

• Receive and process inbound emails to the assistant's address
• Draft, approve, and send outbound emails as the assistant
• Thread-aware conversations
• Custom domain setup with DNS verification

Phone Calls

Your assistant can make and receive phone calls via Twilio.

• Inbound calls — callers reach your assistant's phone number, and it answers with real-time voice conversation powered by ElevenLabs text-to-speech
• Outbound calls — your assistant can call people on your behalf (for example, during guardian verification)
• Transcripts — call recordings are transcribed and stored as conversation history

Channels vs. interfaces

Internally, the system distinguishes between channels and interfaces.

Channels are the six communication transports: vellum, telegram, slack, email, and phone. Every message has a channel.

Interfaces are more specific — they include the channels plus the specific clients used to send the message. The vellum channel has four interfaces: macos (the desktop app), web (the browser), ios (the iPhone and iPad app), and cli (the terminal).

What works where

Not every channel can do everything. Here's what to expect:

Your assistant adapts its output to what the channel supports. If it would normally show you an interactive card, it'll send plain text on Telegram or speak it on a phone call instead.

Same assistant, everywhere

Your assistant's identity, personality, and memory are channel-independent. A conversation that starts on your desktop can be followed up on Telegram. A fact you share over a phone call is remembered in Slack.

What ties it together is the guardian system.

The guardian

The guardian is you — the primary owner of the assistant. Guardians have full access to memories, workspace files, tools, and credentials, and are the only ones who can grant approval for sensitive actions. Channels are how the guardian system stretches that trust across the places you actually live.

Three things the guardian system does on every channel:

• Verifies who's talking. The first time you message your assistant on a new channel, you go through a short challenge-response flow that links that channel identity to your guardian account.
• Routes approvals. When the assistant needs permission to do something sensitive, it asks the guardian. Approvals routed through a channel are always downgraded to one-time grants.
• Gates memory extraction. Long-term memories are only extracted from messages by trusted guardians.

Setting up channels

Web and desktop don't need setup beyond signing in to your Vellum Cloud account (or installing the app, for desktop). Other channels are configured through your assistant. You can say things like:

• “Set up Telegram”
• “Connect to Slack”
• “Set up voice”
• “Provision a phone number”

Your assistant walks you through the setup conversationally.