Give MonstarX tools with MCP connectors

In shortIn Backend → Cloud → Connectors → MCP, add a remote MCP server by name and HTTPS address, or paste a JSON configuration for several at once. MonstarX checks the connection, lists the server's tools, and can then use them in Build mode for that project. Up to 32 servers per project.

MCP (the Model Context Protocol) is a common way for AI tools to offer each other abilities. An MCP server is a service that offers a set of tools: search some documentation, look something up in your company’s systems, run a task. Many products now publish one.

Connect an MCP server to a project, and MonstarX’s builder can use its tools while it works on that app. For example, connect a documentation server and say “check the payment provider’s docs and build the refund flow the way they recommend”.

Before you start

You need the server’s public HTTPS address, from the provider’s documentation. It usually ends in /mcp or /sse.
If the server needs you to sign in, get an access token or API key from the provider.

How do I add an MCP server?

Open your project and click Backend in the top bar, then Cloud.
In Connectors, find the MCP card and click Add server.
Fill in the form:
- Server name — any name you will recognise, like “Docs search”.
- Server URL — the server’s HTTPS address.
- Connection type — Streamable HTTP for current servers, or Legacy SSE if the provider gives you an SSE address.
- Bearer token (optional) — the access token, if the server needs one.
- Custom headers (JSON, optional) — for servers that want their key in a header of their own, such as { "X-Api-Key": "…" }.
Click Connect and check tools. MonstarX connects to the server and lists its tools before it saves anything. If it cannot connect, nothing is saved and it tells you what to check.

Can I add several servers at once?

Yes, if you already have an MCP configuration from another tool. Click Import JSON instead of Add server, paste an mcpServers object and click Connect and check tools:

{
  "mcpServers": {
    "documentation": {
      "url": "https://mcp.example.com/mcp"
    },
    "workspace": {
      "type": "http",
      "url": "https://tools.example.org/mcp",
      "headers": { "Authorization": "Bearer YOUR_ACCESS_TOKEN" }
    },
    "legacy": {
      "type": "sse",
      "url": "https://legacy.example.net/sse"
    }
  }
}

MonstarX checks every server before saving any of them. Each name must be different. Servers that start a program on your computer (a command instead of a url) cannot be imported.

The Import JSON form with an MCP configuration box, a note that command-based servers are not supported, and Connect and check tools and Cancel buttons

How does MonstarX use the tools?

Once a server is connected and enabled, MonstarX knows its tools and when to reach for them. Ask in the chat as you normally would, and mention the server if it helps: “use the Docs search server to check how webhooks work”.

Build mode can look at the tools and use them.
Plan and Chat modes can see which tools there are, but not use them.
Two servers can have tools with the same name — MonstarX keeps them apart.
It works for imported apps too.

How do I manage a connected server?

Each server in the MCP card shows its tool count and these buttons:

Click the tool count to see the tools it offers.
Check connection connects again and refreshes the tool list, for when the provider adds tools.
Disable stops MonstarX from using the server, even in a request that is already running. Enable turns it back on.
Remove deletes the server and its saved credentials, after you confirm.

What is not supported?

Servers that run on your own computer (started with a command), or on a private network or localhost. The address must be a public HTTPS one.
Signing in through a pop-up window (interactive OAuth). Get a token from the provider and paste it as the bearer token instead.
Refreshing a token that expires. When it does, remove the server and add it again with a new token.
MCP resources and prompts, and servers that need to ask MonstarX questions back (sampling or elicitation). Only tools are used.

Good to know

Up to 32 servers per project.
Credentials stay secret. The address and any token or headers are encrypted. They never appear in the chat, in your app’s code or in the published app.
One project only. Servers belong to the project you add them in, and only its owner can add them.

Frequently asked questions

Where do I find an MCP server's address?

In the provider's own documentation, usually under "MCP" or "AI integrations". It is an HTTPS address, often ending in /mcp.

Why cannot MonstarX use the tools in Chat mode?

Tools can change things in other systems, so MonstarX only runs them in Build mode. Chat and Plan can still see which tools a server has.

The server needs me to sign in. What do I do?

Ask the provider for an access token or API key and paste it into Bearer token (optional), or into Custom headers if the provider names a different header.

My token expired. How do I update it?

Remove the server and add it again with the new token. MonstarX does not refresh tokens by itself.

Can my app use these MCP servers?

No. MCP connectors are for MonstarX's builder. To give your app a service, use a connector or ask MonstarX to integrate it with a key in Backend → Secrets. For live public data of a country — weather, transport, registries — use country data, which MonstarX hosts.

Business toolsLet MonstarX use your Google, CRM and project tools.

Use MonstarX from your coding agentThe other way round: your agent uses MonstarX.

ConnectorsGive your app Stripe, Twilio and more.

Build, Plan and Chat modesWhat Build, Plan and Chat mode can do.