Building an MCP server is straightforward with an official SDK, available for several languages.
1. Pick a Small Use Case
Start with one useful tool — for example, looking up an order by ID in your system.
2. Create the Server
Using an SDK, create a server with a name and version, then register a tool with:
- A clear name, such as
get_order. - A description explaining what it does and when to use it.
- An input schema, such as
order_idas a string. - A handler that performs the lookup and returns text or structured content.
3. Choose a Transport
Use stdio for a local server; the SDK handles message framing.
4. Test With an Inspector
Protocol inspector tools connect to your server, list its tools and let you call them manually. Fix schema and output issues here before involving a model.
5. Connect to a Host
Add the server to an MCP-compatible application's configuration, then ask the model something that needs your tool.
6. Iterate
Watch how the model uses the tool. Improve descriptions and outputs where it's confused.
Before Sharing
Add input validation, helpful errors, logging to stderr and documentation. For remote deployment, add authorisation.