Fix ResourceLinkBlock deserialization by adding missing "name" case

src/ModelContextProtocol.Core/Protocol/ContentBlock.cs

@@ -103,6 +103,10 @@ public class Converter : JsonConverter<ContentBlock>
                         text = reader.GetString();
                         break;
 
+                    case "name":
+                        name = reader.GetString();
+                        break;
+
                     case "data":
                         data = reader.GetString();
                         break;

tests/ModelContextProtocol.Tests/Protocol/ContentBlockTests.cs

@@ -0,0 +1,83 @@
+using System.Text.Json;
+using ModelContextProtocol.Protocol;
+
+namespace ModelContextProtocol.Tests.Protocol;
+
+public class ContentBlockTests
+{
+    [Fact]
+    public void ResourceLinkBlock_SerializationRoundTrip_PreservesAllProperties()
+    {
+        // Arrange
+        var original = new ResourceLinkBlock
+        {
+            Uri = "https://example.com/resource",
+            Name = "Test Resource",
+            Description = "A test resource for validation",
+            MimeType = "text/plain",
+            Size = 1024
+        };
+
+        // Act - Serialize to JSON
+        string json = JsonSerializer.Serialize(original, McpJsonUtilities.DefaultOptions);
+
+        // Act - Deserialize back from JSON
+        var deserialized = JsonSerializer.Deserialize<ContentBlock>(json, McpJsonUtilities.DefaultOptions);
+
+        // Assert
+        Assert.NotNull(deserialized);
+        var resourceLink = Assert.IsType<ResourceLinkBlock>(deserialized);
+
+        Assert.Equal(original.Uri, resourceLink.Uri);
+        Assert.Equal(original.Name, resourceLink.Name);
+        Assert.Equal(original.Description, resourceLink.Description);
+        Assert.Equal(original.MimeType, resourceLink.MimeType);
+        Assert.Equal(original.Size, resourceLink.Size);
+        Assert.Equal("resource_link", resourceLink.Type);
+    }
+
+    [Fact]
+    public void ResourceLinkBlock_DeserializationWithMinimalProperties_Succeeds()
+    {
+        // Arrange - JSON with only required properties
+        const string Json = """
+            {
+                "type": "resource_link",
+                "uri": "https://example.com/minimal",
+                "name": "Minimal Resource"
+            }
+            """;
+
+        // Act
+        var deserialized = JsonSerializer.Deserialize<ContentBlock>(Json, McpJsonUtilities.DefaultOptions);
+
+        // Assert
+        Assert.NotNull(deserialized);
+        var resourceLink = Assert.IsType<ResourceLinkBlock>(deserialized);
+
+        Assert.Equal("https://example.com/minimal", resourceLink.Uri);
+        Assert.Equal("Minimal Resource", resourceLink.Name);
+        Assert.Null(resourceLink.Description);
+        Assert.Null(resourceLink.MimeType);
+        Assert.Null(resourceLink.Size);
+        Assert.Equal("resource_link", resourceLink.Type);
+    }
+
+    [Fact]
+    public void ResourceLinkBlock_DeserializationWithoutName_ThrowsJsonException()
+    {
+        // Arrange - JSON missing the required "name" property
+        const string Json = """
+            {
+                "type": "resource_link",
+                "uri": "https://example.com/missing-name"
+            }
+            """;
+
+        // Act & Assert
+        var exception = Assert.Throws<JsonException>(() =>
+            JsonSerializer.Deserialize<ContentBlock>(Json, McpJsonUtilities.DefaultOptions));
+
+        Assert.Contains("Name must be provided for 'resource_link' type", exception.Message);
+    }
+}