Float Parameter Misinterpreted as Single in Function Invocation

[AvatarisAI]

Hi @StephenHodgson ,

I recently started using the OpenAI Chat Completions package, and while things are going well overall, I’m encountering an issue with one of my functions.

The function has 5 parameters, one of which is a float. It seems that the framework incorrectly interprets this float value as single, causing the function invocation to fail when calling:
var funcOutput = await toolCall.InvokeFunctionAsync();

I traced the issue to the following line in Runtime/Common/Function.cs (line 477):
var methodParams = function.MethodInfo.GetParameters(); it's in Runtime/Commmon/Function.cs on line 477

Here’s what happens:

1. The creativity parameter is passed with a value of 0.8 (as shown in requestedArgs):
   

2. However, after evaluating function.MethodInfo.GetParameters(), the parameter is interpreted as single:
   

Since the parameter is defined as float in the function signature, this mismatch causes the invocation to fail.

Could you please take a look at this logic and see if there’s a fix?

Thank you!

Exception I get in function: Runtime/Common/Function.cs (line 392):

System.ArgumentException: Object of type 'System.Double' cannot be converted to type 'System.Single'.
  at System.RuntimeType.CheckValue (System.Object value, System.Reflection.Binder binder, System.Globalization.CultureInfo culture, System.Reflection.BindingFlags invokeAttr) [0x00071] in <ed969b0e627d471da4848289f9c322df>:0 
  at System.Reflection.RuntimeMethodInfo.ConvertValues (System.Reflection.Binder binder, System.Object[] args, System.Reflection.ParameterInfo[] pinfo, System.Globalization.CultureInfo culture, System.Reflection.BindingFlags invokeAttr) [0x00069] in <ed969b0e627d471da4848289f9c322df>:0 
  at System.Reflection.RuntimeMethodInfo.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00040] in <ed969b0e627d471da4848289f9c322df>:0 
  at System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) [0x00000] in <ed969b0e627d471da4848289f9c322df>:0 
  at OpenAI.Function.InvokeInternalAsync[T] (OpenAI.Function function, System.Object[] invokeArgs) [0x00012] in .\Library\PackageCache\com.openai.unity\Runtime\Common\Function.cs:443 
  at OpenAI.Function.InvokeAsync (System.Threading.CancellationToken cancellationToken) [0x000c3] in .\Library\PackageCache\com.openai.unity\Runtime\Common\Function.cs:381 

[StephenHodgson]

Can you show me how you specified your function?

[StephenHodgson]

easy quick fix is just to convert your function signature to use double.

[Function("Executes a task based on the provided input.")]
public static async Task<(bool, string, string)> ExecuteTask(
    [FunctionParameter("Negative prompt for the task. ")] string negativePrompt,
    [FunctionParameter("Input prompt for task execution. ")] string prompt,
    [FunctionParameter("Creativity level between 0 and 1. Lower values are less creative.")] double creativity,
    [FunctionParameter("Specify the name for the output. The name should be concise, use underscores for spaces, and be descriptive, yet not overly lengthy. Example: 'sample_output_name'.")] string outputName,
    [FunctionParameter("Format ratio of the output. Allowed values: '16:9', '9:16', '1:1'.")] string formatRatio)
{
    var operationResult = await GenericService.PerformOperationAsync(negativePrompt, prompt, (float)creativity, formatRatio);
        
    if (operationResult.IsSuccess)
    {
        Debug.Log($"Task initiation successful. Operation ID: {operationResult.TaskId}");

        // Start monitoring for task completion
        var taskOutput = await RetrieveTaskOutput(operationResult.TaskId);
        return taskOutput;
    }
    else
    {
        Debug.LogError($"Task initiation failed. Message: {operationResult.Message} (Status Code: {operationResult.StatusCode})");
        return (false, $"Task initiation failed. Message: {operationResult.Message} (Status Code: {operationResult.StatusCode})", string.Empty);
    }
}

[AvatarisAI]

easy quick fix is just to convert your function signature to use double.

[Function("Executes a task based on the provided input.")]
public static async Task<(bool, string, string)> ExecuteTask(
    [FunctionParameter("Negative prompt for the task. ")] string negativePrompt,
    [FunctionParameter("Input prompt for task execution. ")] string prompt,
    [FunctionParameter("Creativity level between 0 and 1. Lower values are less creative.")] double creativity,
    [FunctionParameter("Specify the name for the output. The name should be concise, use underscores for spaces, and be descriptive, yet not overly lengthy. Example: 'sample_output_name'.")] string outputName,
    [FunctionParameter("Format ratio of the output. Allowed values: '16:9', '9:16', '1:1'.")] string formatRatio)
{
    var operationResult = await GenericService.PerformOperationAsync(negativePrompt, prompt, (float)creativity, formatRatio);
        
    if (operationResult.IsSuccess)
    {
        Debug.Log($"Task initiation successful. Operation ID: {operationResult.TaskId}");

        // Start monitoring for task completion
        var taskOutput = await RetrieveTaskOutput(operationResult.TaskId);
        return taskOutput;
    }
    else
    {
        Debug.LogError($"Task initiation failed. Message: {operationResult.Message} (Status Code: {operationResult.StatusCode})");
        return (false, $"Task initiation failed. Message: {operationResult.Message} (Status Code: {operationResult.StatusCode})", string.Empty);
    }
}

I was trying this as well, and it didn't help me, i get same error, just with "double"...

[StephenHodgson]

in the meantime I can add additional validation to the function call parameter types and downcast if it is available (like double -> float in this case)

[StephenHodgson]

I was trying this as well, and it didn't help me, i get same error, just with "double"...

This should have fixed the signature, just be sure that it actually saves and recompiles to apply the fix.

[AvatarisAI]

I was trying this as well, and it didn't help me, i get same error, just with "double"...

This should have fixed the signature, just be sure that it actually saves and recompiles to apply the fix.

🤔 Hm, now it worked! Thanks!
Weird... Maybe it was really because the previous time it hadn't finished recompiling. I created this thread exactly because switching to double didn’t work for me the previous times. :D

[StephenHodgson]

One other potential fix is to create a type that encapsulates your parameters:

[Serializable]
public class TaskParameters
{
    [JsonProperty("negativePrompt"]
    public string NegativePrompt { get; set; }
   ...
}

This will force it to use the proper types specified in the json schema.

[AvatarisAI]

One other potential fix is to create a type that encapsulates your parameters:

[Serializable]
public class TaskParameters
{
    [JsonProperty("negativePrompt"]
    public string NegativePrompt { get; set; }
   ...
}

This will force it to use the proper types specified in the json schema.

thank you, will do!

[StephenHodgson]

opened a bug report with potential fix: #326