• Who: Anyone who gets an error similar to: “Unexpected token 0 in JSON at position”.
  • What: How to fix the error: “Unexpected token 0 in JSON at position”.
  • With: FileMaker Server 17+
  • Why: Any JSON object that does not properly escape quotations will result in an error.

This happens when you don’t stringify the JSON that you send to the patch http call. A similar issue happens on create via an http call. If the weird character in your JSON is somewhere in the middle of the error message, most likely your JSON is not formatted correctly. Paste your JSON here to see your error:

https://jsonformatter.curiousconcept.com