.NET: [Feature Branch] Migrate state schema updates and support for agents as MCP tools (#1979)

dotnet/src/Microsoft.Agents.AI.DurableTask/State/DurableAgentStateFunctionCallContent.cs

@@ -0,0 +1,63 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Collections.Immutable;
+using System.Text.Json.Serialization;
+using Microsoft.Extensions.AI;
+
+namespace Microsoft.Agents.AI.DurableTask.State;
+
+/// <summary>
+/// Durable agent state content representing a function call.
+/// </summary>
+internal sealed class DurableAgentStateFunctionCallContent : DurableAgentStateContent
+{
+    /// <summary>
+    /// The function call arguments.
+    /// </summary>
+    /// TODO: Consider ensuring that empty dictionaries are omitted from serialization.
+    [JsonPropertyName("arguments")]
+    public required IReadOnlyDictionary<string, object?> Arguments { get; init; } =
+        ImmutableDictionary<string, object?>.Empty;
+
+    /// <summary>
+    /// Gets the function call identifier.
+    /// </summary>
+    /// <remarks>
+    /// This is used to correlate this function call with its resulting
+    /// <see cref="DurableAgentStateFunctionResultContent"/>.
+    /// </remarks>
+    [JsonPropertyName("callId")]
+    public required string CallId { get; init; }
+
+    /// <summary>
+    /// Gets the function name.
+    /// </summary>
+    [JsonPropertyName("name")]
+    public required string Name { get; init; }
+
+    /// <summary>
+    /// Creates a <see cref="DurableAgentStateFunctionCallContent"/> from a <see cref="FunctionCallContent"/>.
+    /// </summary>
+    /// <param name="content">The <see cref="FunctionCallContent"/> to convert.</param>
+    /// <returns>
+    /// A <see cref="DurableAgentStateFunctionCallContent"/> representing the original content.
+    /// </returns>
+    public static DurableAgentStateFunctionCallContent FromFunctionCallContent(FunctionCallContent content)
+    {
+        return new DurableAgentStateFunctionCallContent()
+        {
+            Arguments = content.Arguments?.ToImmutableDictionary() ?? ImmutableDictionary<string, object?>.Empty,
+            CallId = content.CallId,
+            Name = content.Name
+        };
+    }
+
+    /// <inheritdoc/>
+    public override AIContent ToAIContent()
+    {
+        return new FunctionCallContent(
+            this.CallId,
+            this.Name,
+            new Dictionary<string, object?>(this.Arguments));
+    }
+}