Connect Slack to Cogno

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At a glance

Slack is where the work already gets talked about. Connect it, invite the Cogno bot to the channels that matter, and Cogno reads what your team is already saying there — turning messages into suggested tasks you accept with a glance, and reaching members over Slack DM when a task needs their eyes. You don’t file anything; Cogno does.

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Before you start

• You can open Settings in the target workspace. Slack setup is not owner-only — any member who reaches Settings can connect it.
• You can install apps in the Slack workspace you want to connect (or someone who can is available to approve it).
• Cogno only syncs channels the bot is a member of. Public channels can be added from Cogno with one click; for private channels you need to be able to invite the bot in Slack.
• Use a Slack workspace that represents the team, not a personal one, so the members Cogno maps are the people you work with.

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Connect Slack in Cogno

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Update Slack permissions

When Cogno gains a feature that needs a new Slack permission, workspaces that connected earlier keep the permissions they originally approved — Slack grants them at install time and never widens them on its own. Channel actions then fail with a permission error until the workspace approves again. You will see this as an error the first time you use a control that needs the new permission — Cogno names the fix rather than showing Slack’s raw error. On the Slack page, click Update permissions next to the workspace name. Cogno opens Slack’s approval screen; approve it and come back. Your channels and user mappings are untouched — this replaces the credentials in place, unlike Disconnect, which deactivates the mappings and starts the 7-day deletion window. Nothing else waits on this. Reading channels, turning messages into suggested tasks, Slack DMs, user mapping and syncing all run on the permissions approved when the workspace first connected, so they keep working whether or not you update. Only controls that need a newer permission are affected — channel switches under Channels require their channel-management scopes, emoji reaction actions require reactions:write, and agent file uploads require files:write. Adding a channel with /invite @Cogno in Slack works either way.

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What Cogno does with Slack

Once connected, Slack becomes an event source: your messages flow into the loop and Cogno acts on them. Three things happen. The sections below cover what Cogno reads, member mapping, and what happens when you mention the bot.

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What Cogno reads — and what it never reads

Cogno reads only the channels the Cogno bot has joined — public or private. New messages in those channels arrive as they are posted, including replies inside threads, and edits and deletions follow: editing a message updates what Cogno holds, and deleting one removes it. On connect — and again whenever you click Sync data — Cogno backfills up to the 100 most recent messages per connected channel and reads the Slack canvases the bot has access to. Right after you connect, it also reads a sample of recent messages once to seed the workspace’s Memory with context about your team. Direct messages and group DMs are never ingested — Cogno doesn’t turn them into tasks or memory, and replying in a notification DM thread does not start a conversation with Cogno. Removing the bot from a channel stops future reading; what was already read stays.

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Search Slack from a Project

Project-scoped agent runs read Slack directly. Message search calls Slack’s current channel history, and thread reads call Slack for the current replies instead of answering from Cogno’s earlier sync. Search results are mirrored only to mint the numeric message ID used by thread, reply, and reaction tools; that mirror is not the source of the answer. Every provider request is limited to the exact Slack connection and channels selected for the Project. An empty channel filter grants no general Slack access; knowing a message ID does not bypass the filter. Disconnected connections and channels the bot no longer belongs to are excluded. A private channel must be accessible to the bot and selected for the Project. A Project’s channel picker lists only the channels the Cogno bot has joined. To offer a channel there, turn it on under Channels on the Slack integration page first. Search is a case-insensitive text match with optional channel and time bounds, returning at most 100 messages. Live searches have a bounded Slack request budget. If a broad or old search cannot be completed inside it, the agent receives an explicit error and can retry with a channel or tighter time bounds instead of receiving a partial result presented as complete.

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Control agent Slack access

Under Agent tools on the Slack integration page, a workspace owner or admin can set Read Slack and Send to Slack independently for this exact connection: Each capability lists the Tools it grants under the choice, as Tools, and marks each one for the mode in force — a check when it runs without asking, a question mark on a dashed outline when it asks first, struck through when it is blocked: Read Slack covers live message search, current thread retrieval, reading a file shared in a channel the Project reads, listing the Project’s channels on a connection, and looking up Slack users by ID or name to mention them. Channel names and users come from Cogno’s last Slack sync. A file read returns the file’s details and what an agent can take in: the text of a text file or a PDF (up to 20,000 characters), or an image of a picture. A PDF with no text, such as a scan, comes back as an image of its first page; any other file type returns its details with a note that its content was not read. When Slack offers the original file, the read also includes a download link that expires after 15 minutes, so the agent can fetch the exact file, for example to edit it. The link stops working when the run that read the file ends, is checked against the Project’s channels again when it is used, and the Slack credential never leaves Cogno. Existing connections keep this allowed unless an owner or admin changes it. Send to Slack covers posting new plain-text messages, replying to a Slack thread, uploading an Input File or a file the agent produced for the current Task, and adding or removing the Cogno bot’s emoji reactions on Slack messages. A message the agent posts comes back with its message ID, so the agent can continue in that message’s thread, for example a short headline in the channel and the details as a reply. It starts blocked. A policy saved for one connection never grants another. Changes apply to the next run. Disconnecting Slack stops an already-running agent immediately. Send to Slack is the only standing-consent setting for these managed writes; the destination channel must still remain selected for that Project and joined by the Cogno bot. Every file upload targets a stored Slack message and appears inside that message’s thread, including images and files attached to progress or result updates. File uploads are limited to 100 MB and may include a plain-text comment. Cogno can send the exact file named in Input Files, or first attach a file produced during a Task run and then send that attachment. A Project Run without a Task keeps the file it produced on the run itself and sends it from there, without creating a Task. It never treats an arbitrary local path or URL as a trusted attachment, and it rejects files belonging to another Task or workspace. Reaction actions target a stored message ID and use a Slack emoji name such as thumbsup or a workspace custom emoji name. Provider operations are recorded before Slack is called so retries cannot silently repeat a write.

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Add the Cogno bot to channels

Cogno only reads channels the Cogno bot has been added to — nothing else is synced or turned into tasks. There are two ways to connect a channel: Public channels — from Cogno. Under Channels, every public channel the bot could join is listed with a switch. Turn it on and Cogno joins the channel for you; turn it off to leave. Private channels — from Slack. Slack does not let a bot join a private channel by itself, and it does not tell Cogno that a private channel exists until @Cogno has been invited to it. So the invitation happens in Slack: The channel appears under Channels with its switch on as soon as you invite the bot. You do not need to sync, and you do not need to reload the page. Turning a private channel’s switch off works like any other channel — Cogno leaves it. The row stays in the list, dimmed, with its switch off and locked: Slack has no API for a bot to add itself to a private channel, so the only way back on is to invite @Cogno there again. When Cogno joins or leaves a channel, it posts a short notice there so the people in the channel can see that it started — or stopped — reading. Slack’s own join and leave messages are not guaranteed to appear.

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Sync workspace data

Under Channels, each row shows a channel, its member count, and up to five member avatars (Slack users not yet mapped to a member appear dimmed); the switch is on for the channels the Cogno bot has joined, and those rows come first. When there are more than eight channels, a Search channels field appears above the list, which scrolls in place. The list keeps itself current: inviting the Cogno bot to a channel, or removing it, updates the list while you are looking at it. Choose Sync data from the ⋯ menu next to the workspace name to refresh everything else — member lists, topics, and recent messages; the workspace row shows the last sync time with channel and message counts. On a large Slack workspace a sync can take a few minutes; if it fails, the workspace row shows Sync failed with the reason.

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Map Slack users to members

Cogno links each Slack user to a workspace member so that everything it reads from Slack is attributed to the right person. Keep the mapping accurate — Cogno uses it in both directions: to attribute incoming Slack messages, and to reach the right person when it notifies or mentions someone. The picker lists human members only; agent members can’t be mapped. While a Slack user is not mapped, their channel messages still flow in and still become suggested tasks — but they aren’t attributed to a member, and that person receives no DM notifications from Cogno.

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What happens when you mention @Cogno

Conversational replies are unavailable. Mention @Cogno in a connected channel and Cogno replies in the mention’s thread with This feature is now unavailable. If the mention is a top-level message, Cogno starts a thread under it. Cogno does not answer the question or respond to later replies in the thread.

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Disconnect Slack

Disconnecting stops Cogno from reading Slack and deactivates all user mappings. It does not uninstall the Slack app: the Cogno bot stays in its channels on the Slack side until you remove it there.

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What happens to your Slack data after disconnecting

Disconnecting starts a 7-day window. Reconnect the same Slack workspace inside it and everything is where you left it — your channels, your user mappings, and the messages Cogno had read. After the window closes, Cogno deletes the Slack data it holds for that workspace: message bodies, thread and channel records, the Slack canvases it read, and the Slack-to-member mappings. The deletion is permanent. Reconnecting after the window gives you a fresh start: Cogno backfills the 100 most recent messages per channel again, and you map your Slack users again. Suggested tasks and tasks already created from Slack are yours and are not touched — they live on your board, not in the integration.

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Common states

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Reference URLs

• Slack: install and manage apps
• Slack OAuth scopes

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Related docs

• Integrations
• Task statuses — where messages Cogno picks up land on your board.
• Troubleshooting