Issues

• Stdio client stops processing responses after rejecting a malformed response

  area/transportbugP2
  modelcontextprotocol/java-sdk#1157 · Filter by author anilloutombam opened on Oct 2, 2026
  1

• Java client accepts responses with jsonrpc: "1.0"

  area/clientP3
  modelcontextprotocol/java-sdk#1156 · Filter by author anilloutombam opened on Oct 2, 2026

• HttpServletStreamableServerTransportProvider: GET stream sends no status or headers until the first event

  area/serverarea/transportP3
  modelcontextprotocol/java-sdk#1155 · Filter by author remi-sf opened on Oct 1, 2026

• Allow strict validation of CallToolResult.content during deserialization

  area/clientP3
  modelcontextprotocol/java-sdk#1148 · Filter by author kele5555 opened on Sep 29, 2026

• SEP-2640: Skills Extension

  extensionsP3
  modelcontextprotocol/java-sdk#1140 · Filter by author uc4w6c opened on Sep 22, 2026

• McpClientSession/McpServerSession: pending response entries leak when a request times out or is cancelled

  area/clientarea/serverarea/transportbugP2
  Bug

  modelcontextprotocol/java-sdk#1133 · Filter by author Lubaoshuai opened on Sep 13, 2026
  1

• Client request handlers that complete empty send no JSON-RPC response

  area/clientbugP2
  Bug

  modelcontextprotocol/java-sdk#1124 · Filter by author 1fanwang opened on Sep 3, 2026
  5

• ServerCapabilities.logging is added unconditionally, overriding the caller's explicit capabilities

  bugP2ready for work
  Bug

  modelcontextprotocol/java-sdk#1086 · Filter by author srmadscience opened on Aug 11, 2026
  1

• listTools() and the other no-arg list*() methods follow the cursor chain without any bound

  bugP3
  Bug

  modelcontextprotocol/java-sdk#1084 · Filter by author harikrishna8121999 opened on Aug 10, 2026
  1

• McpServerSession never sends a response when a request handler's Mono completes empty — violates JSON-RPC 2.0's one-response-per-request contract

  bugP2ready for work
  Bug

  modelcontextprotocol/java-sdk#1081 · Filter by author ChiragMoradiya opened on Aug 8, 2026
  2

• Add transportContextProvider to McpClient.AsyncSpec

  area/clientarea/transportwaiting for user
  modelcontextprotocol/java-sdk#1075 · Filter by author iuliiasobolevska opened on Aug 1, 2026
  3

  

• Request customizers can't tell which connection a request belongs to

  area/clientarea/transportP3waiting for user
  Enhancement

  modelcontextprotocol/java-sdk#1074 · Filter by author iuliiasobolevska opened on Aug 1, 2026
  3

  

• Allow composing request customizers on the HTTP client transport builders

  area/clientarea/transportP2
  Enhancement

  modelcontextprotocol/java-sdk#1073 · Filter by author iuliiasobolevska opened on Aug 1, 2026 · 2.1
  2

  

• Disable standalone GET SSE Stream option for Streamable HTTP client transport

  enhancementP3
  Enhancement

  modelcontextprotocol/java-sdk#1068 · Filter by author leo237 opened on Jul 21, 2026

• Reject listRoots if not supported by client, without sending any request

  enhancementgood first issueP3
  Enhancement

  modelcontextprotocol/java-sdk#1067 · Filter by author michaelboyles opened on Jul 19, 2026
  2

• Migrate null annotations to jspecify

  enhancementP2ready for work
  Enhancement

  modelcontextprotocol/java-sdk#1066 · Filter by author michaelboyles opened on Jul 18, 2026
  1

• Un-deprecate/add no-arg builders

  enhancementneeds confirmationP3
  Enhancement

  modelcontextprotocol/java-sdk#1065 · Filter by author michaelboyles opened on Jul 18, 2026

• Expose API to inspect and remove inactive server sessions

  area/serverenhancementneeds confirmationP2
  Enhancement

  modelcontextprotocol/java-sdk#1063 · Filter by author ArchForge286 opened on Jul 17, 2026
  3

• Stateful streamable server calls listRoots() unconditionally on roots/list_changed, blocking a servlet thread until requestTimeout when no roots consumer is registered

  bugP2ready for work
  Bug

  modelcontextprotocol/java-sdk#1061 · Filter by author mayur9991 opened on Jul 16, 2026
  2

• SEP-2663: Tasks Extension

  enhancementextensionsP2
  Enhancement

  modelcontextprotocol/java-sdk#1013 · Filter by author localden opened on Jun 6, 2026 · 2.2
  2

• SEP-2577: Deprecate Roots, Sampling, and Logging

  area/clientarea/serverenhancementP1ready for work
  Enhancement

  modelcontextprotocol/java-sdk#1012 · Filter by author localden opened on Jun 6, 2026 · 2.2

• SEP-2575: Make MCP Stateless

  area/transportenhancementP1
  Enhancement

  modelcontextprotocol/java-sdk#1011 · Filter by author localden opened on Jun 6, 2026 · 2.2
  11

• SEP-2567: Sessionless MCP via Explicit State Handles

  area/transportenhancementP1
  Enhancement

  modelcontextprotocol/java-sdk#1010 · Filter by author localden opened on Jun 6, 2026 · 2.2

• SEP-2549: TTL for List Results

  area/mcp-schemaenhancementP1ready for work
  Enhancement

  modelcontextprotocol/java-sdk#1009 · Filter by author localden opened on Jun 6, 2026 · 2.2
  1

• SEP-2468: Recommend Issuer (iss) Parameter in MCP Auth Responses

  area/authorizationenhancementP1ready for work
  Enhancement

  modelcontextprotocol/java-sdk#1008 · Filter by author localden opened on Jun 6, 2026 · 2.2
  1