When you're trying to fix problems with requests and responses in Node.js applications, there are some handy tools that can really help. Here are a few that I think are really useful:

1. Node.js Built-in Debugger

• This tool is simple but works well. You can start your application in debug mode by typing $ node inspect app.js. This lets you set breakpoints so you can look at variable values and see how the program flows.

2. Postman

• This tool is awesome for testing APIs! You can send requests and see the responses. Plus, you can even set up automated tests. It's easy to use and really speeds up the debugging process.

3. morgan

• This middleware tracks requests and logs them to the console. You can set it up to show all sorts of details about incoming requests, which is super helpful when you're trying to fix issues.

4. ndb

• This tool gives you a better debugging experience for Node.js. It's based on Chrome DevTools and has many features, like live reloading, which makes debugging feel more interactive.

Using these tools can save you a lot of time and frustration!