@AI Evy How do i test a function in a multi-prompt agent by itself, without having to go through the the entire workflow or making a call?

Thanks for tagging me @CG. I'll look through relevant sources and get back to you shortly.

Ok @AI Evy I have another question. I keep getting this error "Result: Axios Error: error code: ERR_BAD_REQUEST, error message: Request failed with status code 400 response status: 400 response data: [{"status":400,"message":"1"},"\"start_date\" format is invalid. Must be YYYY-mm-dd like (2025-12-22)"]" how do I get the format correct?

### Answer The error message tells you exactly what format is expected:

YYYY-mm-dd

(e.g.,

2025-12-22

) . [(1) ]() To fix this, ensure the

start_date

parameter in your custom function is being passed as a string in that exact format. In your function's parameter schema, you can define it like this:

json
{
  "type": "object",
  "properties": {
    "start_date": {
      "type": "string",
      "description": "The start date in YYYY-mm-dd format (e.g., 2025-12-22) "
    }
  },
  "required": ["start_date"]
}

Adding a clear description helps the LLM extract and format the date correctly from the conversation. If the LLM is still passing an incorrectly formatted date, you can also update your prompt to explicitly instruct the agent to format dates as

YYYY-mm-dd

before calling the function.

I'm doing a GET function and i'm building a multi-prompt agent. Where should i put the description in my custom function? if i place the variable between curly brackets will it de denoted as a string or do i need to put it in quotes?

Thanks for the follow-up, @CG. I'll get back to you soon.

@AI Evy I’m running into a confusing issue with a GET custom function and date parameters for availability, and I’d really appreciate your help debugging how Retell is building the HTTP request. ### Context I’ve built a multi-prompt agent using Juvonno as the EMR. One of my custom HTTP functions is: - Name:

juvonno_get_availability

- Purpose: get appointment availability from Juvonno - Method:

GET

- Usage: called from

State4_booking_calendar

to find slots for a given day (e.g. “tomorrow at 12 pm”, “Friday at 2 pm”). When I don’t pass any dates, the function returns availability (Juvonno seems to use some default date like

2025-12-22

). But when I try to pass

start_date

and

end_date

so we can search specific days, the API responds with a 400 error saying the date format is invalid – even though the date string looks correct. I’d like help understanding exactly how Retell is mapping function “Arguments” → HTTP query parameters for this GET request, and how I should configure it so Juvonno accepts the dates. --- ### What works (no dates,

Arguments: {}

) In this scenario, my custom function is defined as a GET with no explicit query params configured. Melina calls: ```text Calling tool: juvonno_get_availability Arguments: {} And Juvonno responds successfully with a huge list of slots keyed by "2025-12-22" (this is the behavior I want, but for whatever date the user actually requested): Result: {"list":[ { "staff":{"id":5,"num":"5","first_name":"3D BODY SCAN","last_name":"THERAPY"}, "slots":{"2025-12-22":[ {"available":true,"time":{"time":"10:00","meridiem":"am","interval":10}, "schedule_type":{"code":"11","name":"3D Body Scan","id":8}}, ... ]} }, ... ]}

Thanks for the follow-up, @CG. I'll get back to you soon.