Connect Slack to Claude: 3 checks before it reads

Slack launched its MCP server in February 2026. MCP is a standard plug that lets an AI app search and act inside another tool. Slack lists Claude as a supported client and says only directory-published or internal apps may use it.

Claude's Slack connector is made by Slack, and its claude.com listing carries an Anthropic verified label. Inside Claude, verified connectors show a green tick next to the name. Anthropic's directory page says verification isn't a security audit.

The connector searches and reads messages. Slack's docs say it can also send, schedule and draft messages. Claude's listing and Slack's page both add that it creates canvases, Slack's shared documents.

It signs in as you. You sign in to Slack and approve the app, Slack returns only content you have access to, and Claude inherits each person's permissions. As of October 2026.

3

checks before Claude reads

1

channel for your first test

20 min

start to finish

Slack

At a glance

Signs in as

You

!Approval

Your Workspace Owner or app manager may need to approve

Time

About 20 minutes with the checks

Two people may need to say yes: someone in Slack and, on a Claude Team or Enterprise plan, someone in Claude. Find your row.

Your situation	Who says yes	What you see
Claude Free, Pro or Max	You, if Slack shows for you	Connect to Claude
Claude Team or Enterprise, you are an Owner	You	Connect for your team, or Connect just for me from the arrow
Claude Team or Enterprise, you are a member	A Claude Owner	Team: Request, then Requested. Enterprise: Request, or a note to ask an Owner
Slack approval is on	A Workspace Owner or app manager	A screen to request the app. Slack hasn't published its exact wording
Slack approval is off	Probably you, but Slack's Claude page lists admin approval as a prerequisite, so ask first	Slack's approval screen

On Slack's side, the default is open. Members can install apps without approval unless a Workspace Owner turns on "Only allow pre-approved apps". Slack's own Claude setup page still lists your workspace admin's approval as a prerequisite. The two pages disagree, so if you aren't the Workspace Owner, ask them before you connect.

When approval is on, requests go to Workspace Owners, and to any app managers they appoint.

Workspace Owners can switch approval on. It changes how everyone installs apps, so tell your team first.

1. 1

   In Slack, open Admin › Apps and workflows › App management settings.

2. 2

   Next to Require approved apps, click Edit.

3. 3

   Tick Only allow pre-approved apps, then click Save.

Slack Enterprise+ with Okta and a Claude Team or Enterprise plan uses a different flow, enterprise-managed authorization. Follow Slack's article for that one.

On Claude Team or Enterprise, an Owner adds a connector for the organization and members then connect their own account, per Anthropic's getting-started page. On Team, Request goes to your organization's Owners and becomes Requested. On Enterprise you may see a note to ask an Owner instead.

Anthropic says web connectors are available to all users, but its older Slack page says the Slack connector is for Team and Enterprise plans. If you are on Free, Pro or Max and Slack won't connect, that may be why. If you can't find Slack in Discover on Team or Enterprise, ask your Claude Owner. As of October 2026.

Illustration · as of Oct 2026

If you need someone else's yes, send this.

Do this part on a computer, with Claude's settings open in another window. Shorter steps for Slack and ClickUp together are in the workflow map guide.

If you want Claude to use a separate Slack user instead of you, skip these steps. Use "Connect a tool as the AI user" in give your AI its own login instead, then come back for checks two and three. It uses a private window, so your own Slack sign-in can't slip in.

1. 1

   In the side panel of Claude, click Customize.

2. 2

   Click Connectors.

3. 3

   Click Discover.

4. 4

   Search for Slack and pick the result marked with a green tick.

Illustration · as of Oct 2026

5. 5

   Click Connect to Claude. Slack opens a screen asking you to sign in and approve access.

6. 6

   Sign in to Slack.

7. 7

   Read the access Claude asks for, line by line.

Illustration · as of Oct 2026

8. 8

   If you can untick private channels, DMs or group DMs, untick them. A first test doesn't need them.

9. 9

   Approve it. Slack now shows as connected in Connectors.

Don't use Slack in a chat yet. Do checks two and three first.

Neither Slack's docs nor Claude's docs describe a setting that limits this connector to channels you pick. Public search covers every public channel, even ones you never joined. So "only read #projects" typed into a prompt is a wish.

Slack does split search into four layers. Public channels are the required base. Private channels, DMs and group DMs are optional permissions with user consent. Slack hasn't published whether Claude's approval screen lets you untick them one by one. Anthropic only says to review the access Claude asks for. That's why the connect steps say "if you can".

DiagramFour read layers

Slack

Public channels (base)

Not needed for a first test

Private channels (check what it asks for)DMs (check what it asks for)Group DMs (check what it asks for)

1. Four read layers, with the Slack logo at the top: Public channels (base); Private channels (check what it asks for); DMs (check what it asks for); Group DMs (check what it asks for).
2. The three lower layers sit behind a lock, with the label Not needed for a first test.
3. Real limits: Blocked tools. Optional permissions you approve. Separate Slack user (limits private channels and DMs, not public ones).

Three limits are real, strongest first:

• Block the tools you don't need. Claude lets you choose Always allow, Needs approval, or Blocked for a whole group or for a single tool.
• Approve only the optional permissions you need. Owners and app managers choose which optional permissions to approve, and so do you wherever Slack splits them.
• Give the AI its own Slack user. It sees only the private channels and DMs that user is in. It still searches every public channel. The steps are in give your AI its own login.

The only documented per-channel control is a different product. Claude Tag responds only where it's been added and addressed. As of October 2026 it is a public beta for Team and Enterprise, set up by a Claude Owner. In channels it acts as its own identity, one Claude set up by an admin, not as you.

Now block the private search.

1. 1

   Open Slack in your connector list (Customize › Connectors › Slack).

2. 2

   Find the three tool groups: Interactive tools, Read-only tools and Write/delete tools.

3. 3

   Set the whole Read-only tools group to Needs approval. It can show Always allow when you first open it, so check it.

4. 4

   Inside that group, set Search messages and files (the one that searches public and private conversations) to Blocked. Leave Search public messages and files as it is.

Claude's Slack listing names that search tool slack_search_public_and_private and its public-only sibling slack_search_public. On the connector page they show as Search messages and files and Search public messages and files. Blocking removes the search tool whose name says it covers private conversations. No one has published whether Claude can still open a private channel directly by its ID, Slack's hidden address for it. That is why step 3 puts every read on Needs approval: Claude asks before each read, and you can say no. Check with the limit test.

Illustration · as of Oct 2026

Slack's docs say the connector can send messages to any type of conversation and schedule messages for later. A scheduled message goes out while you aren't watching. So it needs approval like Send message.

In Slack, the Write/delete tools group holds Send message, Schedule message, Create a canvas and Update a canvas. The Interactive tools group holds Create a draft message.

Group or tool	Examples	Set it to
Write/delete tools group	Slack: Send message, Schedule message, Create a canvas, Update a canvas	Needs approval
Read-only tools	Tools that only read or search	Needs approval first. Always allow once you trust it.
Interactive tools	Slack: Create a draft message	Needs approval first. Always allow once you trust it.

The one exception is the tool that searches private conversations. It stays Blocked, per check two. Move the Read-only tools to Always allow only after a clean limit test (in "Your first week"). From then on, Claude reads without asking, so you can no longer say no to a single read. Keep the Write/delete tools group on Needs approval for good.

1. 1

   Open Slack in your connector list (Customize › Connectors › Slack).

2. 2

   Find the three tool groups: Interactive tools, Read-only tools and Write/delete tools.

3. 3

   Set the whole Write/delete tools group to Needs approval.

4. 4

   Set Interactive tools, which holds Create a draft message, to Needs approval.

5. 5

   Check the mode. If your message box has a permission setting, set it to Manual. If it still shows separate Chat and Cowork options, pick Manually approve in Cowork. If you see neither, Claude asks with an Allow once or Always allow prompt.

Illustration · as of Oct 2026

Slack's docs describe drafting as drafting, formatting and previewing messages directly within AI clients. Claude may show the draft in the chat or save it in Slack's Drafts. Slack doesn't document which. Either way, nothing is sent until you approve.

DiagramClaude drafts, you approve

1Claude shows the draft

2Approval promptAllow onceAlways allow

3Message appears in the channel

Write/delete tools

• Send messageNeeds approval
• Schedule messageNeeds approval
• Create a canvasNeeds approval
• Update a canvasNeeds approval

1. Step 1, Claude shows the draft.
2. Step 2, the approval prompt: Allow once or Always allow. Allow once is the choice. Always allow (not for sends) is crossed out.
3. Step 3, the message appears in the channel in Slack.
4. Slack's Write/delete tools group: Send message, Schedule message, Create a canvas and Update a canvas. All four are set to Needs approval.

On Team or Enterprise, an Owner uses the same page (Customize › Connectors › the tool) to limit actions for the whole organization, and individual users can't override it (Anthropic).

Illustration · as of Oct 2026

Test with one channel you pick. Claude can still reach every public channel, so the limit is on you: ask only about that channel and check every answer. Widen after a clean week.

1. 1

   In Claude, start a new chat.

2. 2

   Click + ("Add files, connectors, and more") at the lower left of the message box.

3. 3

   Click Connectors.

4. 4

   Toggle Slack on. Connectors are switched on or off per chat. Check the toggle in every new chat, because Slack may already be on.

Illustration · as of Oct 2026

5. 5

   Paste this into Claude, with your test channel filled in.

If Claude asks before a Slack read, click Allow once. Check three things in each answer. The links open the real messages. Nothing comes from a place you didn't mean to share. Nothing was sent.

Now test your block.

6. 6

   In Slack, create a private channel with only you in it.

7. 7

   Post one made-up word there, for example plum-test-42.

8. 8

   Back in Claude, paste this.

It should find nothing. If it finds your word, switch Slack off in this chat, check that the private search tool shows Blocked, and test again. If it still finds it, disconnect Slack (see "How do I switch it off?").

After one clean week, add one more channel to your questions. Keep every send on Needs approval.

Confirm the setup works:

Do this now0 / 8 done

Slack shows as connected in Customize › ConnectorsThe Write/delete tools group is set to Needs approvalThe tool that searches private conversations is BlockedEvery test answer linked to real messagesThe limit test didn't find my made-up wordClaude showed me a draft and sent nothingClaude's mode is Manual (or Manually approve, if Cowork is still a separate option for you)Claude asked before each Slack read, and I chose Allow once