Add ZoomInfo as a Custom Connector
The settings to use when a third-party app asks you to add a custom MCP server: ZoomInfo's server URL, Streamable HTTP transport, and OAuth sign-in. Plus the manual OAuth fallback.
Rowan BaileySenior Director, ProductSome apps let you add a custom MCP server: you paste a server URL into a connector form and the app handles the rest. This page covers what to enter so ZoomInfo connects on the first try. You don't need to create anything in ZoomInfo first.
Have a native option, or building your own?
If your app is Claude, ChatGPT, Claude Code, Codex, or Cursor, use the marketplace listing or plugin instead. It's one click and needs none of the settings below. If you're building your own agent or integration rather than configuring an existing app, see How to Build Your Own App on the ZoomInfo MCP.
Recommended Settings
Most custom-connector forms ask for the same few things:
| Field | Value |
|---|---|
| Server URL | https://mcp.zoominfo.com/mcp (HTTPS, exactly as written) |
| Transport | Streamable HTTP. Pick this over SSE, and never a local command or stdio; ZoomInfo's server is remote. |
| Authentication | OAuth. Use the app's Connect or Authenticate button and sign in. Leave any client ID and secret fields blank. |
| Headers | None. ZoomInfo uses OAuth, not a static token. |
| Name | Anything you'll recognize, like ZoomInfo. |
The usual flow is: paste the URL, pick Streamable HTTP, save, then click Connect (or Authenticate). The app sends you to the ZoomInfo sign-in, you log in with your normal credentials or SSO, and you approve access. The client discovers ZoomInfo's authorization server from the URL and registers itself, so you don't supply OAuth details or a redirect URI by hand.
When the App Asks for OAuth Details
A few clients, often command-line tools, can't discover and register on their own. They ask for a client ID, a client secret, and sometimes the OAuth endpoints. When that happens, register an app first (How to Build Your Own App on the ZoomInfo MCP walks through it), then fill in:
| Field | Value |
|---|---|
| Client ID / Client Secret | From the app you registered |
| Authorization URL | https://mcp.zoominfo.com/oauth/authorize |
| Token URL | https://okta-login.zoominfo.com/oauth2/default/v1/token |
| Redirect / callback URL | Use the exact value the app shows you, usually a localhost loopback. It has to match the redirect URI on your registered app, character for character. |
Choose user sign-in over a shared service account wherever you can. See User Sign-In vs Service Account for why it matters.
Verify the Connection
Once the connector shows as connected, ask the app something that needs ZoomInfo data:
How many employees does Snowflake have?A healthy connection calls the matching tool and returns live data. If the app reports no tools or a failed connection, the sign-in probably didn't finish. Reconnect and complete the ZoomInfo login.
Troubleshooting
The app rejects the URL.
It must be HTTPS and exactly https://mcp.zoominfo.com/mcp, with no trailing slash or extra path.
Only SSE and Streamable HTTP are offered. Pick Streamable HTTP. SSE is a legacy fallback and works, but Streamable HTTP is the current transport.
"redirect_uri mismatch" during sign-in. This only applies when you registered your own app. The redirect URI in the connector form must match the one on your app exactly, including the port and path.
The connection drops after a few hours. Your ZoomInfo session expired. Reconnect to refresh it.
What's Next
For apps with a native listing or plugin, see the client setup guides. To build your own agent or integration on the MCP server, see How to Build Your Own App on the ZoomInfo MCP. For the full tool list, see the MCP Tools documentation.