Add ModelContextProtocol.Core package (#428)

src/ModelContextProtocol.Core/Protocol/Completion.cs

@@ -0,0 +1,39 @@
+using System.Text.Json.Serialization;
+
+namespace ModelContextProtocol.Protocol;
+
+/// <summary>
+/// Represents a completion object in the server's response to a <see cref="RequestMethods.CompletionComplete"/> request.
+/// </summary>
+/// <remarks>
+/// See the <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/">schema</see> for details.
+/// </remarks>
+public class Completion
+{
+    /// <summary>
+    /// Gets or sets an array of completion values (auto-suggestions) for the requested input.
+    /// </summary>
+    /// <remarks>
+    /// This collection contains the actual text strings to be presented to users as completion suggestions.
+    /// The array will be empty if no suggestions are available for the current input.
+    /// Per the specification, this should not exceed 100 items.
+    /// </remarks>
+    [JsonPropertyName("values")]
+    public string[] Values { get; set; } = [];
+
+    /// <summary>
+    /// Gets or sets the total number of completion options available.
+    /// </summary>
+    /// <remarks>
+    /// This can exceed the number of values actually sent in the response.
+    /// </remarks>
+    [JsonPropertyName("total")]
+    public int? Total { get; set; }
+
+    /// <summary>
+    /// Gets or sets an indicator as to whether there are additional completion options beyond 
+    /// those provided in the current response, even if the exact total is unknown.
+    /// </summary>
+    [JsonPropertyName("hasMore")]
+    public bool? HasMore { get; set; }
+}