Slack
Read messages, find people and send messages from your Slack account in the Companion.
Slack is a personal connection. Each user connects their own account; no Harmony admin role is required.
Messages are sent from your account. To send as Harmony, use Slack — Harmony Bot.
The Companion can find public channels and private channels you belong to. It uses your Slack permissions to read and post messages.
What the Companion can do
| Action | Supported tasks |
|---|---|
| Messages | Send direct messages, post in channels and reply in threads |
| Reading | Read channel messages and thread replies |
| Reactions | Add emoji reactions |
| Channels | Find, list and create channels; invite people |
| People | Find people by name, @handle or email |
| Files | Share text files in channels |
The Companion asks for approval before sending or making changes in Slack, unless the tool is auto-approved. Reading and lookups do not require approval. See Tool approval.
Use channel names, @handles or email addresses, such as #sales-team or @anna. IDs are not required.
The Companion reads Slack messages on request. It does not import your message history into Harmony.
Connect Slack
- Open Marketplace → Apps in Harmony.
- Open Slack.
- Select Install.
- Select Install just for me to open Slack authorization.
- Check the Slack workspace and permissions, then select Allow.
Slack appears under Marketplace → Installed after authorization.
Allow popups for Harmony, then select Install just for me again.
If your Slack workspace requires app approval, request it from a Slack admin before connecting.
Use it in the Companion
Example requests:
- "Summarise this week's messages in #sales-team."
- "Send @anna the action items from my last call."
- "Create a private channel called customer-onboarding and invite [email protected]."
When prompted, review the action and select Approve.
Use it in automations
Automations send Slack messages from your account. Describe the trigger, recipient and message to the Companion:
- "When a customer call summary is ready, post it in #customer-calls."
- "Every Friday at 16:00, post this week's customer calls in #team-sales."
See Create an automation.
Direct Slack steps send automatically. A Run agent step requires the Slack tool; otherwise, the run stops with Needs permission. See Permission needed.
Automations are active when saved by default. Request a draft to review recipients and messages before switching it on.
Slack permissions
| Slack permissions | Purpose |
|---|---|
channels:read, groups:read, im:read, mpim:read | Find channels and conversations |
channels:history, groups:history, im:history, mpim:history | Read messages and threads |
chat:write | Send messages from your account |
reactions:write | Add emoji reactions |
channels:write, groups:write | Create channels and invite people |
users:read, users:read.email | Find people by name or email |
files:write | Share files in channels |
team:read | Read workspace details |
Manage or remove Slack
Open Marketplace → Installed → Slack.
- Test Connection — check the connection.
- Re-authenticate — authorize again if Slack revokes access or the app is removed.
- Delete — disconnect your account from Harmony. The Companion and automations can no longer use it.
Deleting the connection does not uninstall the app from Slack. Remove it separately in Slack's app management.
Troubleshooting
The Companion cannot post in a channel
The Companion sends from your Slack account. Open the channel in Slack and check that you can post there. Join the channel if needed, then retry in the Companion.
The Companion cannot find a channel
Use the channel name, such as #sales-team. For private channels, check that the Slack account connected to Harmony is a member.
The Companion cannot find a person
Try the email address or @handle shown in their Slack profile. The person must belong to the Slack workspace connected to Harmony.
Slack is not connected
Check Marketplace → Installed. If Slack is listed, open it, select Re-authenticate and complete Slack authorization. If it is missing, connect Slack again.
An automation run stopped with Needs permission
The automation's agent needs access to the Slack tool. Open the stopped run and select Settings next to Run this step as. Add the Slack tool, save, then select Apply and re-run. See Permission needed.