As many users have flagged there is a bug in tools - there is no option to add parameters any more and no documentation on what the new way is.

Hi there! 👋 I understand you're experiencing issues with editing tools configuration and adding function parameters in Vapi. While I couldn't find specific information about a bug preventing these actions, I can share what I know about the current method for configuring tools. According to the documentation, when setting up a function-type tool, you should include a

parameters

object that describes the parameters expected by your function. Here's an example of how a tool configuration should look:

json
{
    "type": "function",
    "messages": [
        {
            "type": "request-start",
            "content": "Checking the weather forecast. Please wait..."
        }
    ],
    "function": {
        "name": "get_weather",
        "parameters": {
            "type": "object",
            "properties": {
                "location": {
                    "type": "string"
                }
            }
        },
        "description": "Retrieves the current weather for a specified location."
    },
    "async": false,
    "server": {
        "url": "https://your-weather-api.com/weather"
    }
}

Vapi did recently update their tool schema to use a

function

property with

id

and

function

details instead of the older

tool

and

toolBody

properties [according to the changelog](https://docs.vapi.ai/changelog/2025/1/22). For more detailed information, you can check the [Vapi Custom Tools Documentation](https://docs.vapi.ai/tools/custom-tools). If you're still experiencing issues after following these guidelines, it might indeed be a bug that hasn't been documented yet. Could you share more details about what specifically happens when you try to add parameters? Sources: - [Vapi changelog](https://docs.vapi.ai/changelog/2025/1/22) - [Vapi Custom Tools Documentation](https://docs.vapi.ai/tools/custom-tools)

Its not editable

It's definitely a bug that's introduced last few days, may be since Thursday when the UI no longer have the section for adding/modifying parameters

It will fixed today

@Pen 💻 @tongsitat @Manu Can you guys try it and let me know how it goes?

Sure 😊