Building an MCP server so Claude can query my SaaS analytics directly

#ai #mcp #typescript #saas

Last week I shipped a Model Context Protocol (MCP) server for my analytics SaaS. Now Claude Desktop, Cursor, and any MCP compatible client can query traffic, revenue, and funnel data directly.

This is a walkthrough of how I built it, what worked, and a couple of patterns that surprised me.

What MCP is, briefly

MCP is a protocol that lets AI clients invoke tools and read resources from external servers. Think of it as REST for LLM tool calling, with a stable schema and discovery.

Server skeleton

import { Server } from '@modelcontextprotocol/sdk/server/index.js'
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js'

const server = new Server({
  name: 'zenovay',
  version: '1.0.0',
}, {
  capabilities: {
    tools: {},
    resources: {}
  }
})

Defining tools

server.setRequestHandler('tools/list', async () => ({
  tools: [
    {
      name: 'get_traffic',
      description: 'Get pageview and visitor counts for a site over a date range',
      inputSchema: {
        type: 'object',
        properties: {
          site: { type: 'string' },
          from: { type: 'string' },
          to: { type: 'string' }
        },
        required: ['site', 'from', 'to']
      }
    }
  ]
}))

The pattern that surprised me: structured returns

Way better than raw JSON: return a short natural language summary plus the data. Claude uses the summary for its response and the JSON for follow up questions.

What I did not expect

Users started asking Claude to do things I had not built dashboards for:

"Compare my paid traffic conversion rate this week vs last week"
"Which 5 pages had the biggest week over week drop in pageviews"
"Summarize what changed in my funnel completion rate over the last 30 days"

Claude does this by chaining multiple tool calls. I did not need to build any of those views. The tools are atomic, Claude composes.

This is the part I think is genuinely new about MCP. The interface is the LLM, the backend is just well shaped tools.

Install

npm install -g @zenovay/mcp then add to your Claude Desktop config.

Site: zenovay.com

Open source MCP server work happening here too? Curious what patterns others have found.

Valerio

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