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Channels

Open an agent's settings and go to the Channels tab. Each row is a way messages can reach the agent. Inbound messages create or continue a thread; the agent runs with whatever tools you've granted on the Tools tab.

In-app chat

Thread — controls whether this agent appears in the in-app agent picker (the "Pick an agent…" list when a thread isn't already bound to an agent). On by default.

Turning Thread off does not remove the agent from the sidebar Agents list, and people can still start in-app threads via that agent's overview composer or the hover new-thread shortcut on its row. Slack, email, schedules, webhooks, and other channels are configured separately — they keep working regardless of this toggle.

Messaging & email

Slack

OAuth into a workspace. Choose which channels to listen in, allow DMs or not, and set listen mode to @mentions only or all messages. The agent needs Slack read/send tool grants to reply in Slack.

Telegram

Connect a Telegram bot (bot token). Users message the bot; each chat maps to an agent thread. The dialog links to t.me/your-bot when connected.

WhatsApp

Provision a dedicated WhatsApp number for this agent (Twilio-backed). Registration can take a few minutes after you connect; inbound texts start threads. Proactive outbound messages need the Send via WhatsApp tool grant.

Gmail

OAuth a Gmail inbox. Inbound mail on that inbox creates threads; the agent can read and send from that address when email tools are enabled. Separate from the Stacker-hosted email address below.

Email

A Stacker-hosted address for this agent (shown on the Channels row once set up). Anyone can email it; inbound messages become threads without connecting Gmail. Manage auto-reply behavior from the Email setup dialog.

Programmatic & voice

Webhook

Add one or more inbound webhook URLs. POST JSON to start or continue a thread from your backend, Zapier, or an automation. Requests can be HMAC-signed when a webhook secret is configured.

Voice

Enable real-time voice conversations (ElevenLabs). Users talk to the agent in the thread UI when voice is active on the agent.

Schedules

Schedules wake the agent on a cron with a prompt you describe in plain language (e.g. "Every weekday at 9am, review open support tickets and flag anything stale"). The UI parses that into a cron expression you confirm before saving.

You can add multiple schedules per agent. Optionally run each tick in a new thread instead of reusing the same one. Scheduled runs are not interactive — the agent cannot show tool-approval cards during a schedule tick; grant tools upfront on the Tools tab.

How threads tie together

Every channel routes inbound traffic into the agent's thread list. Slack thread timestamps, email Message-IDs, webhook payloads, and chat sessions each map to a stable thread key so follow-up messages land in the same conversation.

View and manage threads on the agent's Threads tab — filter by channel, pin important ones, or archive old conversations. Pausing an agent stops new runs; disconnecting a channel stops new messages from that source without deleting history.