Build MCP Server
Once you can ship a tiny server, any internal system — tickets, metrics, deploys — can show up as tools in every MCP client.
Building an MCP server is writing an API that every AI app already knows how to call.
Visual Workflows
Start here — scroll inside each diagram frame to explore, then use + / − to zoom up to 200% if needed.
Overview
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Scroll inside the frame to explore · use + / − to zoom up to 200%
Do not skip Inspector
Scroll inside the frame to explore · use + / − to zoom up to 200%
If Inspector fails, Cursor will fail too — with a worse error.
Key Takeaways
- 1.Pick an SDK: Python mcp or TypeScript @modelcontextprotocol/sdk. Define 1–3 tools with tight schemas, then implement call_tool.
- 2.Run locally on stdio first; test with MCP Inspector before any host. Only then add the server to mcp.json and try it inside Cursor.
- 3.Start with one tool. A server that greets you is enough to prove initialize, schemas, and stdio.
- 4.Add real APIs only after Inspector is green.
Learn elsewhere
- →Wiring discovered tools into an agent loop — last module
- →Remote deploy — Remote MCP
Real Example
Scenario
You wrap two Datadog tools — query_metrics and list_alerts — test them in Inspector, then every team agent can watch production.
What you would do
In Model Context Protocol, apply Build MCP Server to this scenario: You wrap two Datadog tools — query_metrics and list_alerts — test them in Inspector, then every team agent can watch production. Identify the inputs, run the technique, validate the output, and note one thing you would monitor in production.
Commands
Commands to Remember
pip install mcpnpx @modelcontextprotocol/inspectorstdio_server() for local firstAdd to mcp.json only after Inspector passes
Cheat Sheet
Quick recap
quick ref- •SDK → tools → Inspector → mcp.json
- •One tool is a complete first server
- •stdout stays JSON-RPC only
- •HTTP and auth come after local works
Common Mistakes
- ✕Jumping to Cursor before Inspector works
- ✕Five tools on day one
- ✕Blocking the event loop with sync HTTP calls