Empty custom tool call argument when payload gets ...
# supportf
Floris
05/02/2025, 6:49 AMI'm building a room service assistant which helps a guest compile an order before it's submitted via a custom tool call. This works great when I add two items. But when I add a third item, the arguments for the tool call are empty. You can clearly see it in the attached call id. I try to place an order with 3 items first which triggers the createOrder tool call with empty arguments. I then remove an item from the order and try again. This time it triggers the createOrder tool call with arguments. I'm not sure what's wrong. Is there a max arguments payload or something?
Call id: 101ee0b5-7b50-451e-b72e-a1f876eaf2d1
v
Vapi Support Bot
05/02/2025, 6:51 AMYes, there appears to be a payload size limit affecting your tool calls. According to [Discord discussions](https://discord.com/channels/1211482211119796234/1342521496920395878), Vapi has a request body size limit of approximately 100KB, which can cause issues when payloads get too large.
Try reducing your payload size by:
- Limiting the amount of data sent in each order
- Removing unnecessary fields from your order objects
- Splitting large orders into multiple smaller tool calls
Sources:
- [Discord discussion about payload size limits](https://discord.com/channels/1211482211119796234/1342521496920395878)
- [Discord report about empty arguments with large payloads](https://discord.com/channels/1211482211119796234/1334666797932089405)
f
Floris
05/02/2025, 6:53 AMCould someone from the @User please have a look? I need this fixed rather urgent and it doesn't seem like I can do something about it from my end.
Floris
05/02/2025, 8:08 AM@Shubham Bajaj ?
c
Chiranjeet Mishra
05/02/2025, 8:34 PMlooking into it.
Chiranjeet Mishra
05/02/2025, 9:00 PMHere floor is, I just logged into the shared call id and created the order function JSON schema. The function JSON Schema is complex, not easy. Ideally based on prompt transcription and tool JSON schema and similarity search. Models are supposed to send the right parameters, but you know models are still black and white and boxes, so allow me some time to review it again to see what can be done for your use case by dropping down the nesting levels or making it flatten parameters tool.
s
Shubham Bajaj
05/05/2025, 12:08 PM@Floris , I wanted to check if passing nested level properties is really important, flatten properties will work for you?
f
Floris
05/06/2025, 6:45 AM@Shubham Bajaj I don't think I can flatten the properties. I need to keep track of what modifications were made to certain order items.
p
prantheman
05/07/2025, 9:54 PMDid you ever end up fixing this @Shubham Bajaj dealing with the same issues
prantheman
05/07/2025, 9:54 PMWhen I have a longer list of objects to send in the args, the entire args object is empty
prantheman
05/07/2025, 10:31 PM@Floris
s
Shubham Bajaj
05/08/2025, 2:44 AM@Floris @prantheman I apologize for the delay in my response. I am still in the process of completing my work on this matter. I will require approximately one to two days more for this issue investigation. Once I have completed, I will promptly provide you with potential solutions or alternatives.
f
Floris
05/12/2025, 1:44 PMAny progress on this @Shubham Bajaj ?
s
Shubham Bajaj
06/18/2025, 5:27 PMHey @Floris and @prantheman
Shubham Bajaj
06/18/2025, 5:27 PMYou have to increase the max tokens limit to 500 or 1000 and then this will be resolved.
f
Floris
06/18/2025, 5:31 PMHow can you do that, @Shubham Bajaj ?
p
prantheman
06/19/2025, 3:11 PMThanks
c
Chiranjeet Mishra
06/20/2025, 2:21 PMMarking this ticket as Solved ✅