Issues

• A tool behind DelegatingMcpServerTool advertises a non-object outputSchema to pre-2026-07-28 clients (regression from 1.4.1)

  bug
  modelcontextprotocol/csharp-sdk#1916 · Filter by author AdCodicem opened on Oct 10, 2026

• UseStructuredContent: with the default serializer options, structuredContent omits a null property that outputSchema requires

  bug
  modelcontextprotocol/csharp-sdk#1915 · Filter by author AdCodicem opened on Oct 10, 2026

• Stdio server never exits after stdin EOF once a client has sent subscriptions/listen (2026-07-28)

  modelcontextprotocol/csharp-sdk#1914 · Filter by author oleksandrdubyna88 opened on Oct 9, 2026

• Reserved URI-template expansion throws for supplementary Unicode characters

  modelcontextprotocol/csharp-sdk#1913 · Filter by author Coding-Professional opened on Oct 9, 2026

• Track support for SEP-2127 MCP Server Cards

  modelcontextprotocol/csharp-sdk#1912 · Filter by author tarekgh opened on Oct 8, 2026

• Per-tool task support metadata in 2.x (replacement for Tool.Execution.TaskSupport)

  modelcontextprotocol/csharp-sdk#1911 · Filter by author nagavitalp opened on Oct 6, 2026

• WithTools<T>() + MapMcp() keeps every host alive after disposal (AIFunctionFactory's static descriptor cache holds the tool's create options)

  modelcontextprotocol/csharp-sdk#1904 · Filter by author migruiz opened on Oct 2, 2026
  1

• [Question] Is McpServerHandlers.CallToolWithAlternateHandler appropriate for InputRequiredResult

  modelcontextprotocol/csharp-sdk#1902 · Filter by author alzimmermsft opened on Oct 2, 2026

• SDK 2.2.0 - McpClient.ServerInfo throws when optional 2026-07-28 serverInfo metadata is absent

  bug
  modelcontextprotocol/csharp-sdk#1901 · Filter by author anushree1808 opened on Oct 2, 2026 · 2.x
  1

• ClaimsPrincipal parameter injection sample request

  modelcontextprotocol/csharp-sdk#1899 · Filter by author hansmbakker opened on Oct 1, 2026

• Tools registered with WithTools keep a disposed service provider in memory

  modelcontextprotocol/csharp-sdk#1898 · Filter by author yasmoradi opened on Sep 29, 2026
  1

• JSON property-name casing is inconsistent between JSON-RPC envelope and request params

  help wantedP3
  modelcontextprotocol/csharp-sdk#1897 · Filter by author nagavitalp opened on Sep 28, 2026
  4

• Resource template with several comma-separated variables in one expression binds the whole value to the first variable

  modelcontextprotocol/csharp-sdk#1896 · Filter by author Laurianti opened on Sep 28, 2026

• Stdio client on Windows: dispose returns before the server tree exits, and a request sent during dispose never completes

  modelcontextprotocol/csharp-sdk#1894 · Filter by author MarcelRoozekrans opened on Sep 27, 2026
  1

• [Proposal] Declarative tool registration & runtime filtering for version gating (#1557)

  modelcontextprotocol/csharp-sdk#1881 · Filter by author ump45nose opened on Sep 17, 2026

• MCP Client: Add bounded connection-establishment recovery with end-to-end timeout and closure guarantees

  enhancement
  modelcontextprotocol/csharp-sdk#1879 · Filter by author anushree1808 opened on Sep 16, 2026

• csharp-sdk graded A (93/100) on OpenTrustBench, badge inside

  modelcontextprotocol/csharp-sdk#1871 · Filter by author gautamkishore opened on Sep 11, 2026

• MCP Protocol-Version Ceiling for the C# Client SDK

  enhancement
  modelcontextprotocol/csharp-sdk#1868 · Filter by author anushree1808 opened on Sep 11, 2026

• Document ClientOAuthOptions.ScopeSelector usage

  modelcontextprotocol/csharp-sdk#1867 · Filter by author z0rimo opened on Sep 11, 2026
  1

• Support explicit OAuth authorization when MCP initialization succeeds anonymously

  modelcontextprotocol/csharp-sdk#1866 · Filter by author Aaronontheweb opened on Sep 10, 2026
  2

• Configure McpServerToolCreateOptions via WithTools

  enhancement
  modelcontextprotocol/csharp-sdk#1865 · Filter by author adrianm64 opened on Sep 9, 2026
  2

• Add support for the Skills extension (SEP-2640)

  modelcontextprotocol/csharp-sdk#1863 · Filter by author PederHP opened on Sep 9, 2026

• StreamableHttpClientSessionTransport loses a correlated JSON-RPC error in a chunked HTTP 200 response

  bug
  modelcontextprotocol/csharp-sdk#1862 · Filter by author anushree1808 opened on Sep 8, 2026
  1

• Stateful connection is intermittent.

  bug
  modelcontextprotocol/csharp-sdk#1861 · Filter by author khteh opened on Sep 8, 2026

• .net 9 targeting .net 10 packages

  modelcontextprotocol/csharp-sdk#1859 · Filter by author sleepydog999 opened on Sep 7, 2026
  2