A utility module for creating Model Context Protocol (MCP) servers declaratively.
npm install mcp-client-routerimport { DeclarativeMCPServer } from "mcp-client-router/declarative-server";
// Create a server declaratively
const server = new DeclarativeMCPServer({
name: "my-server",
version: "1.0.0",
// Define tools as arrays of arguments
tools: [
[
"greeting",
{ message: "string" },
async ({ message }) => ({
content: [{ type: "text", text: `Hello, ${message}!` }],
}),
],
[
"farewell",
{ name: "string" },
async ({ name }) => ({
content: [{ type: "text", text: `Goodbye, ${name}!` }],
}),
],
],
// Define prompts
prompts: [
[
"welcome",
{ name: "string", formality: { type: "string", default: "CASUAL" } },
async ({ name, formality }) => {
const text =
formality === "FORMAL"
? `Dear ${name}, welcome to our service.`
: `Hi ${name}! Welcome aboard!`;
return {
messages: [{ role: "assistant", content: { text } }],
};
},
"A welcome prompt template",
],
],
// Define resources
resources: [
[
"docs/readme",
async () => ({
contents: [
{
uri: "docs/readme",
text: "This is the documentation readme file.",
},
],
}),
],
],
});
// Connect to a transport
await server.connect(transport);new DeclarativeMCPServer(options);name(string): The name of the serverversion(string): The version of the servertools(array): An array of tool definitionsprompts(array): An array of prompt definitionsresources(array): An array of resource definitions
[
name, // string: name of the tool
paramSchema, // object: parameter schema
handler, // function: async function to handle the tool call
description, // string (optional): description of the tool
];[
name, // string: name of the prompt
paramSchema, // object: parameter schema
handler, // function: async function to handle the prompt
description, // string (optional): description of the prompt
];[
uri, // string: URI of the resource
handler, // function: async function to handle the resource request
];ISC