.Net: Bug: Failed to serialize arguments to Json

[mhackermsft]

Describe the bug
Exact same issue as #11511 but the issue is not resolved by using a specific SK or Microsoft.Extensions.AI package.

I am running into the exact same issue with Semantic Kernel 1.46.0 and ModelContextProtocol .01.0-Preview.9. I have the Microsoft.Extensions.AI 9.4.0-preview.1.25207.5 installed.

Error message:
Microsoft.SemanticKernel.KernelFunction[0]
Function playwright-playwright_get arguments: Failed to serialize arguments to Json
System.NotSupportedException: JsonTypeInfo metadata for type 'Microsoft.SemanticKernel.KernelArguments' was not provided by TypeInfoResolver of type 'Microsoft.SemanticKernel.AbstractionsJsonContext'. If using source generation, ensure that all root types passed to the serializer have been annotated with 'JsonSerializableAttribute', along with any types that might be serialized polymorphically.
at System.Text.Json.ThrowHelper.ThrowNotSupportedException_NoMetadataForType(Type type, IJsonTypeInfoResolver resolver)
at System.Text.Json.JsonSerializerOptions.GetTypeInfoInternal(Type type, Boolean ensureConfigured, Nullable`1 ensureNotNull, Boolean resolveIfMutable, Boolean fallBackToNearestAncestorType)
at System.Text.Json.JsonSerializerOptions.GetTypeInfo(Type type)
at Microsoft.SemanticKernel.KernelFunctionLogMessages.LogFunctionArgumentsInternal(ILogger logger, String pluginName, String functionName, KernelArguments arguments, JsonSerializerOptions jsonSerializerOptions)

Seeing similar message with another MCP server:
Microsoft.SemanticKernel.KernelFunction[0]
Function spotify-SpotifyPlayback arguments: Failed to serialize arguments to Json
System.NotSupportedException: JsonTypeInfo metadata for type 'Microsoft.SemanticKernel.KernelArguments' was not provided by TypeInfoResolver of type 'Microsoft.SemanticKernel.AbstractionsJsonContext'. If using source generation, ensure that all root types passed to the serializer have been annotated with 'JsonSerializableAttribute', along with any types that might be serialized polymorphically.
at System.Text.Json.ThrowHelper.ThrowNotSupportedException_NoMetadataForType(Type type, IJsonTypeInfoResolver resolver)
at System.Text.Json.JsonSerializerOptions.GetTypeInfoInternal(Type type, Boolean ensureConfigured, Nullable`1 ensureNotNull, Boolean resolveIfMutable, Boolean fallBackToNearestAncestorType)
at System.Text.Json.JsonSerializerOptions.GetTypeInfo(Type type)
at Microsoft.SemanticKernel.KernelFunctionLogMessages.LogFunctionArgumentsInternal(ILogger logger, String pluginName, String functionName, KernelArguments arguments, JsonSerializerOptions jsonSerializerOptions)

Here are my project references:

all runtime; build; native; contentfiles; analyzers; buildtransitive

Expected behavior
The tool is successfully called and the LLM can use it to generate a response.

Platform

• Language: C#
• Source: [e.g. NuGet package version 0.1.0, pip package version 0.1.0, main branch of repository]
• AI model: gpt-4o
• IDE: Visual Studio
• OS: Windows

[SergeyMenshykh]

Hi @mhackermsft,

Semantic Kernel 1.46.0 is built against the ModelContextProtocol .01.0-Preview.8 nuget package. SK was just updated to the latest ModelContextProtocol .01.0-Preview.9 today - #11582. We may release a new SK version either at the end of this week or early next week.

Meanwhile, to get unblocked, consider downgrading to the ModelContextProtocol .01.0-Preview.8 nuget package.

[mhackermsft]

I downgraded to the ModelContextProtocol .01.0-Preview.8 nuget package but I am still getting the same error:

Microsoft.SemanticKernel.KernelFunction[0]
Function playwright-playwright_press_key arguments: Failed to serialize arguments to Json
System.NotSupportedException: JsonTypeInfo metadata for type 'Microsoft.SemanticKernel.KernelArguments' was not provided by TypeInfoResolver of type 'Microsoft.SemanticKernel.AbstractionsJsonContext'. If using source generation, ensure that all root types passed to the serializer have been annotated with 'JsonSerializableAttribute', along with any types that might be serialized polymorphically.
at System.Text.Json.ThrowHelper.ThrowNotSupportedException_NoMetadataForType(Type type, IJsonTypeInfoResolver resolver)
at System.Text.Json.JsonSerializerOptions.GetTypeInfoInternal(Type type, Boolean ensureConfigured, Nullable`1 ensureNotNull, Boolean resolveIfMutable, Boolean fallBackToNearestAncestorType)
at System.Text.Json.JsonSerializerOptions.GetTypeInfo(Type type)
at Microsoft.SemanticKernel.KernelFunctionLogMessages.LogFunctionArgumentsInternal(ILogger logger, String pluginName, String functionName, KernelArguments arguments, JsonSerializerOptions jsonSerializerOptions)

[SergeyMenshykh]

Hi @mhackermsft, please try downgrading to the ModelContextProtocol.01.0-Preview.7 NuGet package. If that does not work, could you please create a console app that reproduces this issue, as it is not reproducible on our side?

[mhackermsft]

downgrading to 7 didn't resolve the issue. I have a demo that reproduces the issue consistently at: https://github.com/mhackermsft/SKMCPDemo.

<PackageReference Include="Microsoft.Extensions.Configuration" Version="9.0.4" />
<PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="9.0.4" />
<PackageReference Include="Microsoft.Extensions.Configuration.FileExtensions" Version="9.0.4" />
<PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="9.0.4" />
<PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="9.0.4" />
<PackageReference Include="Microsoft.Extensions.Logging" Version="9.0.4" />
<PackageReference Include="Microsoft.Extensions.Logging.Console" Version="9.0.4" />
<PackageReference Include="Microsoft.SemanticKernel" Version="1.46.0" />
<PackageReference Include="Microsoft.SemanticKernel.Abstractions" Version="1.46.0" />
<PackageReference Include="Microsoft.SemanticKernel.Core" Version="1.46.0" />
<PackageReference Include="ModelContextProtocol" Version="0.1.0-preview.9" />

The MCPClient project attempts to use a Playwright MCP server from: https://github.com/executeautomation/mcp-playwright

Downgrading the ModelContextProtocol version does not resolve the issue.

trce: Microsoft.SemanticKernel.KernelFunction[0]
Function playwright-playwright_fill arguments: Failed to serialize arguments to Json
System.NotSupportedException: JsonTypeInfo metadata for type 'Microsoft.SemanticKernel.KernelArguments' was not provided by TypeInfoResolver of type 'Microsoft.SemanticKernel.AbstractionsJsonContext'. If using source generation, ensure that all root types passed to the serializer have been annotated with 'JsonSerializableAttribute', along with any types that might be serialized polymorphically.
at System.Text.Json.ThrowHelper.ThrowNotSupportedException_NoMetadataForType(Type type, IJsonTypeInfoResolver resolver)
at System.Text.Json.JsonSerializerOptions.GetTypeInfoInternal(Type type, Boolean ensureConfigured, Nullable`1 ensureNotNull, Boolean resolveIfMutable, Boolean fallBackToNearestAncestorType)
at System.Text.Json.JsonSerializerOptions.GetTypeInfo(Type type)
at Microsoft.SemanticKernel.KernelFunctionLogMessages.LogFunctionArgumentsInternal(ILogger logger, String pluginName, String functionName, KernelArguments arguments, JsonSerializerOptions jsonSerializerOptions)