How to document web errors
Step 1 – Determine the error to document
- Firefox/Gecko's error messages: https://github.com/mozilla/gecko-dev/blob/master/js/src/jsshell.msg
- Edge/Chakra's error messages: https://github.com/Microsoft/ChakraCore/blob/master/lib/Parser/rterrors.h
- Chrome/v8's error messages: https://chromium.googlesource.com/v8/v8.git/+/refs/heads/main/src/execution/messages.h
Step 2 – Check the existing error documentation
- Depending on which type of error you want to write about, you can take a closer look at these pages.
- You might want to copy the content of an existing page to kick off your new page.
Step 3 – Create the new error page
- To create a new page, see the instructions in our how to create a page guide.
Step 4 – Document the error
- Either use a copied structure from one of the existing error documents or start from scratch. Your choice!
- You should have at least:
- A syntax box containing the message as thrown in different browsers.
- The error type.
- A text that explains why this error happened and what its consequences are. Go beyond the thrown message.
- Examples showcasing the error (there might be more than one!) and an example showing how to fix the code.
- Pointers to other reference material on MDN Web Docs.
Step 5 – Get the content reviewed
After you've created the error page, submit it as a pull request. A member of our review team will be assigned automatically to review your page.