ChatGPT's Problem With JSON Open up the ChatGPT UI [https://chat.openai.com/] and ask it for some JSON. Chances are you will get a response like you can see in the cover photo above: a JSON object presented to you in markdown format, with some text to either side explaining what the

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Learn how to structure JSON responses in ChatGPT with function calling. Prompt engineering can help ensure consistent JSON format. Function calling allows better control over the data returned.

How to Structure JSON Responses in ChatGPT with Function Calling

great, thanks for “function call” feature. I’ve faced a lot of issues while dealing with inconsistent JSON data by ChatGPT even I provided the very specific prompt to tell it how the outpout should be formatted!

I was using Langchain &amp; Zod to do this but now I think it will be better

In the early days, before the ChatGPT Plugins, I have made a small POC called BridgeGPT. It used the 3.5 API to get JSON responses and manage a bash shell.
This way you can basically do anything on your computer, as long as you can do it into a bash shell (so, anything, if you give ChatGPT some knowledge of handy scripts).
I had exactly the predictability problem (sometimes you get proper JSON objects along with simple text) and fixed it by using string parsing with regular expressions.
This trick works almost everytime, and if a JSON object is not returned, the whole chat is prompted again to the AI, enriching the text with reinforcement phrases for outputting a JSON object until it works.
I gave up with BridgeGPT mainly because of costs and because it is a full time job to make it reliable, but I still think it would be a great product.