Connect Gmail, Google Sheets and Slack to Your App Builder
Mythex Connectors link Gmail, Google Sheets, Slack, Notion and more to the chat agent, with no API keys in your code. How it works, setup, and limits.
Mythex Team · · 4 min read
Mythex can now act on the tools you already use. Connect Gmail, Google Sheets, Slack, Notion or hundreds of other apps once, then ask the agent in chat to read a sheet, send an email or post a message. Your account is linked to Mythex, not to your code: the agent never sees the credential, and nothing lands in your repository.
What it does
A connector is a link between your Mythex account and an account you hold somewhere else. Once it's in place, the agent can use that account on your behalf when you ask it to in chat. For example:
Read the "Q4 pipeline" sheet and build me a dashboard from it
The agent finds the right action for the task, checks the arguments it needs, and runs it. Behind that are four tools:
| Tool | What it does |
|---|---|
AppListConnections | Lists the apps you have connected |
AppSearchTools | Finds the right action for a task, and the arguments it takes |
AppConnect | Gives you a link to connect an app it needs |
AppRun | Runs one action against your connected account |
If the agent needs an app you haven't connected, the turn stops on a card with a Connect button instead of a link buried in a paragraph. Press it, approve in the tab that opens, and come back — the card notices and turns to Connected. Ask again and the agent carries on. It won't guess at your data or make up a spreadsheet while it waits.
Why we built it
Building something useful usually means touching real data: a sheet of leads, an inbox, a team channel. The usual route is to create an API key, paste it into a settings file, and hope it never ends up in a commit. That's fiddly for a non-developer and risky for everyone.
Connectors take the key out of the picture. You sign in with the provider the way you would anywhere else (OAuth, in the jargon), and the credential stays with Mythex's connection service:
- Encrypted at rest
- Never written into your project, your
.env, or generated code - Never sent to the sandbox your app is built in — the sandbox asks the server to make the call and gets the result back
- Removed when you disconnect or delete your account
How to use it
Connect an app
- Open Connectors. It's in the left sidebar under Projects, and inside a project you can also press + next to the message box and choose Connectors. It opens over whatever you were doing, so you don't lose your place.
- Search for the app. Search covers the whole catalogue, not just what's on screen.
- Click Connect. The provider's sign-in page opens in a new tab, so your project and any half-written message stay put.
- Approve access there.
- Come back to the Mythex tab. The app shows a green dot and reads Connected.
Approve every permission the provider asks for. Google in particular splits access by product: approving Gmail but not Drive leaves the connection half-working, and the agent will report ACCESS_TOKEN_SCOPE_INSUFFICIENT when it tries to use it. The fix is to disconnect, connect again, and approve everything.
Ask for what you want
Once connected, just say it in plain language. You don't have to name the tool or the action.
Disconnect
Open Connectors, switch to Connected in the left rail, and hover the app. Disconnect revokes Mythex's access with the provider immediately. Anything the agent already built stays; it just can no longer reach that account.
Planning never sends an email
In Ask and Plan mode the agent can only look. It can list your connections and research what they could do, but it can't run an action or start a connection. That makes Plan mode a safe place to work out what you want before anything touches your inbox or your channels — more on that in plan before you build.
Custom MCP servers
Not everything is in the catalogue. Connectors → Custom MCP takes the URL of any MCP server — your own, your company's, or one a vendor gave you. Fill in a name and the URL, choose how it authenticates, and press Add & authorize:
- If the server asks you to sign in, its own consent screen opens in a tab.
- If it wants a static token, paste it into the Bearer token field. A stored token is never shown again.
- If it needs nothing, it connects straight away.
The tool list is read at that moment, so a wrong URL or a refused token fails in the form rather than halfway through a build. You can switch a server off without removing it, and Refresh re-reads its tools after you change them. Sign-ins are renewed in the background. You can add up to ten servers per account.
Limits
- Connections belong to you, and are shared across all your projects.
- Not every listed app can connect yet. A few in the catalogue don't support it and show as unavailable.
- Rate limits apply to how often the agent can call a connected app, to protect the quota on your own provider account.
- If a provider revokes or expires the grant — common after a password change or a workspace permission change — the agent will say the app needs reconnecting. Disconnect and connect again.
This post is about what the agent can do for you in chat. For the full picture, read the Connectors docs.