#!/usr/bin/env node
import { Server } from "@modelcontextprotocol/sdk/server/index.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import {
CallToolRequestSchema,
ListToolsRequestSchema,
} from "@modelcontextprotocol/sdk/types.js";
import { RestClient, RestToolFactory } from "@mcp/rest-utils";
import { stringTools } from "./tools.js";
const STRING_BASE_URL = "https://string-db.org";
// Create REST client for STRING API
const client = new RestClient({
baseUrl: STRING_BASE_URL,
defaultHeaders: {
"Content-Type": "application/x-www-form-urlencoded",
},
timeout: 30000,
retries: 3,
});
// Custom tool factory with form-encoded body transformation
class StringToolFactory extends RestToolFactory {
async executeTool(config: any, args: any): Promise<any> {
try {
const endpoint = typeof config.endpoint === "function"
? config.endpoint(args)
: config.endpoint;
let requestOptions = config.transformRequest
? config.transformRequest(args)
: { method: config.method || "GET" };
// Transform body to form-encoded format for POST requests
if (requestOptions.body && requestOptions.method === "POST") {
const formBody = new URLSearchParams();
Object.entries(requestOptions.body).forEach(([key, value]) => {
formBody.append(key, String(value));
});
requestOptions = {
...requestOptions,
body: formBody.toString(),
};
}
const response = await (this as any).client.request(endpoint, requestOptions);
const data = config.transformResponse
? config.transformResponse(response.data)
: response.data;
return {
content: [
{
type: "text",
text: JSON.stringify(data, null, 2),
},
],
};
} catch (error: any) {
const errorMessage = error.message || String(error);
const errorResponse = error.response ? `\n${JSON.stringify(error.response, null, 2)}` : "";
return {
content: [
{
type: "text",
text: `Error: ${errorMessage}${errorResponse}`,
},
],
isError: true,
};
}
}
}
// Create tool factory
const toolFactory = new StringToolFactory(client);
// Convert tool configs to MCP tools
const tools = stringTools.map((config) => toolFactory.createTool(config));
// Server implementation
const server = new Server(
{
name: "string-mcp-server",
version: "1.0.0",
},
{
capabilities: {
tools: {},
},
}
);
// List available tools
server.setRequestHandler(ListToolsRequestSchema, async () => {
return { tools };
});
// Handle tool execution
server.setRequestHandler(CallToolRequestSchema, async (request) => {
const { name, arguments: args } = request.params;
// Find the tool configuration
const toolConfig = stringTools.find((tool) => tool.name === name);
if (!toolConfig) {
return {
content: [
{
type: "text",
text: `Error: Unknown tool: ${name}`,
},
],
isError: true,
};
}
// Execute the tool using the factory
return toolFactory.executeTool(toolConfig, args || {});
});
// Start the server
async function main() {
const transport = new StdioServerTransport();
await server.connect(transport);
console.error("STRING MCP Server running on stdio");
}
main().catch((error) => {
console.error("Fatal error in main():", error);
process.exit(1);
});
