A very simple script: written in Tasklemon, and written with the built-in Node.js APIs

clear-example.js

// Tasklemon
home.children.forEach(child => {
	if (child.extension === 'tmp') child.delete();
});


// Node.js
const fs = require('fs');
const os = require('os');
const path = require('path');

const folderPath = os.homedir();
fs.readdirSync(folderPath).forEach(childName => {
	if (path.parse(childName).ext === '.tmp') {
		const absolutePath = path.join(folderPath, childName);
		fs.unlinkSync(absolutePath);
	}
});