refactor: several improvements (#132)

- js export expression
- check args regarding run-agent/run-tool

tools/demo_js.js

@@ -11,7 +11,7 @@
  * @property {string[]} [array_optional] - Define a optional string array property
  * @param {Args} args
  */
-exports.run = function run(args) {
+exports.run = function (args) {
   let output = `string: ${args.string}
 string_enum: ${args.string_enum}
 string_optional: ${args.string_optional}

tools/execute_js_code.js

@@ -4,7 +4,7 @@
  * @property {string} code - Javascript code to execute, such as `console.log("hello world")`
  * @param {Args} args
  */
-exports.run = function run({ code }) {
+exports.run = function ({ code }) {
   let output = "";
   const oldStdoutWrite = process.stdout.write.bind(process.stdout);
   process.stdout.write = (chunk, _encoding, callback) => {