Build Custom MCP Servers

When to Build Custom MCP Servers

Build custom MCP servers when:

Native servers don't exist for your specific APIs
You need custom business logic beyond what existing servers provide
You have proprietary systems that require custom integration

If pre-built servers meet your needs, consider Native MCP servers or Composio's platform instead.

Getting Started

The Quick Start workspace includes a Next.js app in the apps/mcp/app/ directory that you can use to expose your MCP servers. Each MCP server you create will be exposed on a separate route on this app.

Creating from a template

You can add a custom MCP server template from our template library for common use cases using the CLI.

inkeep add --mcp [server-name]

This will automatically add a custom MCP server template to your Quick Start workspace. After customizing and deploying it, you can register it.

Using Vercel's Template

If you want to create a custom MCP server, you can use Vercel's Next.js MCP template as a starting point.

Create a new directory in your project's apps/mcp/app/ directory with your desired server name (e.g. apps/mcp/app/my-email-mcp/mcp).

mkdir -p apps/mcp/app/[server-name]/mcp

Copy the template route.ts file from the Vercel MCP template into apps/mcp/app/[server-name]/mcp/route.ts.

Modify the template route.ts file with your desired tools and resources.

Set the basePath of the createMcpHandler to /[server-name].

Running locally

pnpm dev

This will start the server on port 3006.

Deploying to Vercel

Follow the instructions in Deploy to Vercel. If you have already deployed to Vercel, you can simply update the deployment by pushing to the same repository.

Note

Enable Fluid compute and set maxDuration to 800 in apps/mcp/app/[server-name]/[transport]/route.ts if you're on a Pro or Enterprise plan and have long-running operations.