.Net: Some fixes to clean up after previous PR's (#3745)

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### Contribution Checklist

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- [ ] The code builds clean without any errors or warnings
- [ ] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [ ] All unit tests pass, and I have added new tests where possible
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Author: markwallace-microsoft

dotnet/src/Extensions/TemplateEngine.Handlebars/HandlebarsPromptTemplate.cs

@@ -1,6 +1,5 @@
 // Copyright (c) Microsoft. All rights reserved.
 
-using System;
 using System.Collections.Generic;
 using System.Threading;
 using System.Threading.Tasks;
@@ -23,7 +22,6 @@ public HandlebarsPromptTemplate(PromptTemplateConfig promptConfig, ILoggerFactor
         this._loggerFactory = loggerFactory ?? NullLoggerFactory.Instance;
         this._logger = this._loggerFactory.CreateLogger(typeof(HandlebarsPromptTemplate));
         this._promptModel = promptConfig;
-        this._parameters = new(() => this.InitParameters());
     }
 
     /// <inheritdoc/>
@@ -54,22 +52,6 @@ public async Task<string> RenderAsync(Kernel kernel, ContextVariables variables,
     private readonly ILoggerFactory _loggerFactory;
     private readonly ILogger _logger;
     private readonly PromptTemplateConfig _promptModel;
-    private readonly Lazy<IReadOnlyList<KernelParameterMetadata>> _parameters;
-
-    private List<KernelParameterMetadata> InitParameters()
-    {
-        List<KernelParameterMetadata> parameters = new(this._promptModel.InputParameters.Count);
-        foreach (var p in this._promptModel.InputParameters)
-        {
-            parameters.Add(new KernelParameterMetadata(p.Name)
-            {
-                Description = p.Description,
-                DefaultValue = p.DefaultValue
-            });
-        }
-
-        return parameters;
-    }
 
     private Dictionary<string, string> GetVariables(ContextVariables variables)
     {
@@ -89,7 +71,5 @@ private Dictionary<string, string> GetVariables(ContextVariables variables)
 
         return result;
     }
-
     #endregion
-
 }

dotnet/src/InternalUtilities/planning/Extensions/KernelFunctionMetadataExtensions.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft. All rights reserved.
 
+using System;
+using System.Collections.Generic;
 using System.Linq;
 
 #pragma warning disable IDE0130
@@ -11,6 +13,55 @@ namespace Microsoft.SemanticKernel.Planning;
 /// </summary>
 internal static class KernelFunctionMetadataExtensions
 {
+    private const string SuccessfulResponseCode = "200";
+    private const string SuccessfulResponseDescription = "Success";
+
+    /// <summary>
+    /// Creates a <see cref="JsonSchemaFunctionView"/> for a function.
+    /// </summary>
+    /// <param name="function">The function.</param>
+    /// <param name="jsonSchemaDelegate">A delegate that creates a JSON Schema from a <see cref="Type"/> and a semantic description.</param>
+    /// <param name="includeOutputSchema">Indicates if the schema should include information about the output or return type of the function.</param>
+    /// <returns>An instance of <see cref="JsonSchemaFunctionView"/></returns>
+    public static JsonSchemaFunctionView ToJsonSchemaFunctionView(this KernelFunctionMetadata function, Func<Type?, string?, KernelJsonSchema?> jsonSchemaDelegate, bool includeOutputSchema = true)
+    {
+        var functionView = new JsonSchemaFunctionView
+        {
+            Name = $"{function.PluginName}_{function.Name}",
+            Description = function.Description,
+        };
+
+        var requiredProperties = new List<string>();
+        foreach (var parameter in function.Parameters)
+        {
+            var schema = parameter.Schema ?? jsonSchemaDelegate(parameter.ParameterType, parameter.Description);
+            if (schema is not null)
+            {
+                functionView.Parameters.Properties.Add(parameter.Name, schema);
+            }
+            if (parameter.IsRequired)
+            {
+                requiredProperties.Add(parameter.Name);
+            }
+        }
+
+        if (includeOutputSchema)
+        {
+            var functionResponse = new JsonSchemaFunctionResponse
+            {
+                Description = SuccessfulResponseDescription
+            };
+
+            var schema = function.ReturnParameter.Schema ?? jsonSchemaDelegate(function.ReturnParameter.ParameterType, SuccessfulResponseDescription);
+            functionResponse.Content.JsonResponse.Schema = schema;
+
+            functionView.FunctionResponses.Add(SuccessfulResponseCode, functionResponse);
+        }
+
+        functionView.Parameters.Required = requiredProperties;
+        return functionView;
+    }
+
     /// <summary>
     /// Create a manual-friendly string for a function.
     /// </summary>