Trying to understand the trade offs between when to use JSON mode instead of Function Calling? The documentation says JSON mode will always produce valid JSON. And at the same time it says Function Calling is “more likely” to return the right function parameters than in the previous models. Previo…

(I work on JSON mode at OpenAI) JSON mode is always enabled for the generation of function arguments, so those are guaranteed to parse. JSON mode is opt in for regular messages. Note that JSON mode sadly doesn’t guarantee that the output will match your schema (though the model tries to do this a…

Using the JSON mode, which is an inbuilt feature specifically for the purpose of creating a JSON, makes more sense in your situation. Don’t forget to add the line 'Return the output as JSON" to the system prompt when using the mode, so that the ystem does not throw up an error

Does it consistently return the same JSON structure?

For me, it’s been fairly consistent today. Haven’t had any problems or exceptions thrown

Hello, I still have such issues (not valid JSON or completely other format) on around 10 to 20% of my function calls. Example function : [image] Should return a json with field “command” inside. I have in return the format below, which is incorrect and not parseable. [image] Any help on thi…

As this topic has a noted solution closing this topic. Please open a new topic for new questions.

JSON mode vs Function Calling

API

kjordan November 8, 2023, 3:55am 6

Appreciate your work, JSON mode solves so many problems parsing the JSON responses, especially the unescaped symbols. Good work

1 Like

Topic		Replies	Views
Question about Function Calling & JSON mode API api , function-calling , json-mode	4	3037	December 19, 2023
Malformed Function Calling JSON response Bugs	5	2812	December 18, 2023
Function calling vs tools vs JSON output API	2	1901	April 18, 2024
Json output different from normal output API json	1	827	February 19, 2025
Functions not always returning a valid JSON object Bugs gpt-4 , functions , function-calling	4	2719	November 12, 2023

JSON mode vs Function Calling

Related topics