Post to Slack, in whichever channel you say.
An answer nobody reads is not an answer. Have it delivered to Slack, where the team already is.
https://mcp.heymetra.com/mcp
1. Install the HeyMetra app in your Slack workspace
On the Connections screen choose Slack. Slack shows you what the app may do (post messages, and list channels so it can ask you which one), and you approve it there. You are back in HeyMetra when it is done.
One install covers the whole workspace. You do not connect Slack again per channel, and there is nothing to choose here.
2. Invite the app to any PRIVATE channel you want to use
Public channels need nothing: the app can post to them without joining. A private channel is different: type /invite @HeyMetra in it. Until you do, HeyMetra cannot see that the channel exists, so it will not be offered.
This is the step people skip and then wonder why a channel is missing from the list. If a private channel is not offered, it has not been invited.
3. Ask for something to be sent, and name the channel
Say what you want posted. Your assistant asks which channel, then shows a card with the exact text and the exact channel before anything is sent. Approve it and it goes; until then nothing has left HeyMetra. It posts what you asked for, when you ask, and nothing here posts on a timer.
4. Check it from the Connections screen
The send button beside the connection posts a fixed test message, so you can confirm delivery works without composing anything.
Add HeyMetra once and it is there in every conversation. The address is the same everywhere:
https://mcp.heymetra.com/mcp
npx add-mcp https://mcp.heymetra.com/mcpadd-mcp is a third-party installer that writes the configuration for Claude Code, Codex, Cursor, Antigravity, VS Code and seventeen other agents. It infers the name from the address, so the server lands as heymetra. Run against this endpoint before it was written here.
Claude — Settings → Customize → Connectors → Add custom connector
Paste the address above into Settings → Customize → Connectors → Add custom connector.
On Team and Enterprise plans only an owner can add it, under Organization settings.
Full walkthrough: heymetra.com/mcp/claude/
ChatGPT — Settings → Security and login → Developer mode, then chatgpt.com/plugins
Paste the address above into Settings → Security and login → Developer mode, then chatgpt.com/plugins.
The address has to end in /mcp here.
Full walkthrough: heymetra.com/mcp/chatgpt/
Grok — grok.com/connectors → New Connector → Custom
Paste the address above into grok.com/connectors → New Connector → Custom.
XAI calls this “bring your own MCP”.
Full walkthrough: heymetra.com/mcp/grok/
Perplexity — Settings → Connectors → Custom connector → Remote
Paste the address above into Settings → Connectors → Custom connector → Remote.
Perplexity documents it as a Pro, Max and Enterprise feature.
Full walkthrough: heymetra.com/mcp/perplexity/
Claude Code — claude mcp add --transport http
claude mcp add --transport http heymetra https://mcp.heymetra.com/mcpOr a .mcp.json in the project root; /mcp inside a session shows what connected.
Full walkthrough: heymetra.com/mcp/claude-code/
Codex — ~/.codex/config.toml
[mcp_servers.heymetra]
url = "https://mcp.heymetra.com/mcp"Under an [mcp_servers.] section, then codex mcp login.
Full walkthrough: heymetra.com/mcp/codex/
Cursor — ~/.cursor/mcp.json, or .cursor/mcp.json in a project
{
"mcpServers": {
"heymetra": { "url": "https://mcp.heymetra.com/mcp" }
}
}Leave the static OAuth fields empty; HeyMetra does not need them.
Full walkthrough: heymetra.com/mcp/cursor/
Antigravity — ~/.gemini/config/mcp_config.json, or .agents/mcp_config.json in a project
{
"mcpServers": {
"heymetra": { "serverUrl": "https://mcp.heymetra.com/mcp" }
}
}The key is serverUrl, not url, unlike every other JSON client.
Full walkthrough: heymetra.com/mcp/antigravity/
Send a message to a Slack channel you name. You see the exact text first, and it is posted only once you approve. Everyone in that channel sees it, and it cannot be unsent.
Propose a change to this account. Nothing is sent until you approve it, and HeyMetra cannot undo it afterwards.
Permissions are switched on per connection, and one you leave off is a tool your assistant never sees.
| Permission | What it covers | Changes anything? |
|---|---|---|
| Included with the connection | What HeyMetra needs to set the connection up, and nothing more. It cannot be switched off on its own; to withdraw it, remove the connection. | No, read only |
| Send messages | Let your assistant post to this channel, with your approval each time. Turn it off and only the test button can reach it. | Yes — every change waits for your approval |
| Full account access | Lets your assistant read anything in this account to answer your questions. The figures are the provider's own, not ones HeyMetra has checked. It can also propose changes: none is applied until you approve it, and HeyMetra cannot undo one afterwards. | Yes — every change waits for your approval |
What each permission lets an assistant do, in full
- Send a message to a Slack channel you name. You see the exact text first, and it is posted only once you approve. Everyone in that channel sees it, and it cannot be unsent.
- Ask anything about this account and get the answer from its live data. Reads only, and the figures are the provider's own rather than ones HeyMetra has checked.
- Propose a change to this account. Nothing is sent until you approve it, and HeyMetra cannot undo it afterwards.
Anything that would change something comes back as a proposal you approve, inside bounds that live in code rather than in a prompt: at most 20 messages a rolling day, counted separately from account changes, and an approval that expires after 30 minutes. How that works.
A channel you use every day is not in the list.
Why: It is private, and the HeyMetra app has not been invited to it. Slack does not reveal private channels an app is not in.
Fix: Open that channel and type /invite @HeyMetra, then ask again.
Your assistant says it cannot choose a channel, or posts nothing at all.
Why: Some assistants remember what HeyMetra could do from when they first connected, and do not notice that it has changed.
Fix: Start a new conversation in your assistant so it picks up what HeyMetra can do now.
A message went to the wrong channel.
Why: The channel is named on the approval card, and approving is what sends it. So a message in the wrong place was approved for that place.
Fix: Read the destination line on the card before approving; it names the channel, not an id. HeyMetra cannot unsend a Slack message afterwards, and neither can Slack.
The app was removed from Slack and sends now fail.
Why: Uninstalling the app in Slack revokes the token HeyMetra holds. The connection remains on the Connections screen and stops working.
Fix: Connect Slack again from the Connections screen. The same channels become available as soon as the install is back.
Install the app once into your Slack workspace. There is no channel to pick while connecting: the install reaches every public channel in your workspace, plus any private one you invite it to. When you ask for something to be sent, your assistant asks which channel, shows you the exact text and the exact channel, and nothing leaves until you approve it. Everyone in that channel sees what is posted and a posted message cannot be unsent. HeyMetra can list your channels so your assistant can ask which one, and it cannot read message history.
About Slack
Slack is where your team already works. Connecting it gives your assistant somewhere to post what you ask it to post, and it asks which channel every time, because choosing the channel is choosing who reads it.
The reason to read Slack through HeyMetra rather than through a server that only knows Slack is everything else it can answer in the same breath:
Ads — Google Ads · Meta
Analytics — Google Analytics 4 · Google Search Console · PostHog
Ecommerce — Shopify · Trendyol · WooCommerce
Revenue & CRM — Stripe · HubSpot · Zoho CRM · Zoho SalesIQ · Zoho Marketing Automation
Mobile — AppsFlyer · RevenueCat · Adapty · App Store Connect
Work — Google Calendar · Google Meet · Jira
Channels — Slack · Telegram
The full catalogue is at heymetra.com/connectors/.
- Slack connector page
- HeyMetra — what the product is
- Setup for every assistant
- Security and limits
- Pricing
- HeyMetra's own repository
Built by Zeisoft, who make HeyMetra. Not affiliated with Slack. This README is generated from HeyMetra's live connector catalogue and refreshed daily; corrections are welcome as issues.