Custom MCP Servers
Beyond the official catalog, CatalEx lets admins connect a custom MCP server — a remote Model Context Protocol server that brings an internal or third-party tool into CatalEx. Once registered, its tools appear alongside the official integrations and can be added to your agents.
Only Admins and Owners can add a custom MCP server to a workspace. Members can connect their own credential to one that already exists, but can't register new servers.
Adding a custom MCP server
On the Tools page, click + Add custom MCP and fill in:
| Field | Notes |
|---|---|
| Name | A short name for the server (e.g. "Internal Wiki MCP"). |
| Description | Optional, up to 80 characters — agents use it to decide when to reach for the tool. |
| Server URL | The server's HTTPS endpoint (e.g. https://mcp.example.com/sse). |
| Authentication | None, Token, or OAuth (see below). |
| Fixed headers | Optional header/value pairs sent with every request. |
Authentication options
- None — the server needs no auth.
- Token — you provide a personal token. It's stored encrypted and never shown again.
- OAuth — the server uses OAuth. If it supports dynamic client registration, no extra setup is needed; otherwise you'll add a Client ID and Client Secret.
Discover and create
For None and Token auth, CatalEx offers Discover tools — it connects to the server and lists the tools it exposes so you can preview them, then Create registers the server. For OAuth, you Continue to the consent screen instead.
Managing a custom MCP
Once registered, a custom MCP card supports:
- Review & approve — approve newly discovered tools before agents can use them.
- Refresh — re-discover the server's tools (for example after you add new ones).
- Delete — remove the server and its tools for everyone in the workspace (this can't be undone).
Using it with an agent
A custom MCP's tools behave like any other tool: add them to an agent from its Tools tab, and set per-action guardrails so sensitive actions require your approval.
FAQ
What's the difference between a custom MCP and an official integration? Official integrations are pre-built and maintained by CatalEx. A custom MCP is a server you host or point to — it lets you bring tools CatalEx doesn't offer out of the box.
Can members add a custom MCP? No — only admins and owners register servers. Members can, however, connect their own token or OAuth credential to a server an admin has already added.
Is my token safe? Personal tokens are stored encrypted and are never displayed again after you save them.