Add ModelContextProtocol.Core package (#428)

src/ModelContextProtocol.Core/Protocol/InitializeRequestParams.cs

@@ -0,0 +1,61 @@
+using System.Text.Json.Serialization;
+
+namespace ModelContextProtocol.Protocol;
+
+/// <summary>
+/// Represents the parameters used with a <see cref="RequestMethods.Initialize"/> request sent by a client to a server during the protocol handshake.
+/// </summary>
+/// <remarks>
+/// <para>
+/// The <see cref="InitializeRequestParams"/> is the first message sent in the Model Context Protocol
+/// communication flow. It establishes the connection between client and server, negotiates the protocol
+/// version, and declares the client's capabilities.
+/// </para>
+/// <para>
+/// After sending this request, the client should wait for an <see cref="InitializeResult"/> response
+/// before sending an <see cref="NotificationMethods.InitializedNotification"/> notification to complete the handshake.
+/// </para>
+/// <para>
+/// See the <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/">schema</see> for details.
+/// </para>
+/// </remarks>
+public class InitializeRequestParams : RequestParams
+{
+    /// <summary>
+    /// Gets or sets the version of the Model Context Protocol that the client wants to use.
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// Protocol version is specified using a date-based versioning scheme in the format "YYYY-MM-DD".
+    /// The client and server must agree on a protocol version to communicate successfully.
+    /// </para>
+    /// <para>
+    /// During initialization, the server will check if it supports this requested version. If there's a 
+    /// mismatch, the server will reject the connection with a version mismatch error.
+    /// </para>
+    /// <para>
+    /// See the <see href="https://spec.modelcontextprotocol.io/specification/">protocol specification</see> for version details.
+    /// </para>
+    /// </remarks>
+    [JsonPropertyName("protocolVersion")]
+    public required string ProtocolVersion { get; init; }
+
+    /// <summary>
+    /// Gets or sets the client's capabilities.
+    /// </summary>
+    /// <remarks>
+    /// Capabilities define the features the client supports, such as "sampling" or "roots".
+    /// </remarks>
+    [JsonPropertyName("capabilities")]
+    public ClientCapabilities? Capabilities { get; init; }
+
+    /// <summary>
+    /// Gets or sets information about the client implementation, including its name and version.
+    /// </summary>
+    /// <remarks>
+    /// This information is required during the initialization handshake to identify the client.
+    /// Servers may use this information for logging, debugging, or compatibility checks.
+    /// </remarks>
+    [JsonPropertyName("clientInfo")]
+    public required Implementation ClientInfo { get; init; }
+}