Fix System.String JSON serialization error in MCP Remote SSE handler#2713
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Fix System.String JSON serialization error in MCP Remote SSE handler#2713
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Register McpJsonUtilities type resolver with ASP.NET Core's HTTP JSON options. CreateSlimBuilder disables reflection-based JSON, causing Results.BadRequest(string) in the MCP SDK's legacy SSE handler to fail with missing TypeInfo for System.String.
reakaleek
approved these changes
Feb 16, 2026
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Register McpJsonUtilities type resolver with ASP.NET Core's HTTP JSON
options. CreateSlimBuilder disables reflection-based JSON, causing
Results.BadRequest(string) in the MCP SDK's legacy SSE handler to fail
with missing TypeInfo for System.String.