Issues

• mcp-apps-demo fails to build on main and is incompatible with the linked UI Inspector

  MCP-UI-Org/mcp-ui#223 · Filter by author SunilWang opened on Sep 22, 2026

• Invitation to test MCPay with an MCP project

  MCP-UI-Org/mcp-ui#219 · Filter by author hizyyo opened on Sep 5, 2026

• Python: create_ui_resource() raises ValidationError under mcp 2.0 (resource uri is now str, not AnyUrl)

  MCP-UI-Org/mcp-ui#216 · Filter by author vvlrff opened on Aug 18, 2026

• Reference sandbox proxy (scripts/proxy/index.html) uses stale postMessage protocol → AppFrame timeout / blank card

  MCP-UI-Org/mcp-ui#213 · Filter by author forge-witt3rd opened on Jul 17, 2026

• Unhandled Error: Not connected rejection when AppRenderer sends host-context-change to a torn-down sandbox

  MCP-UI-Org/mcp-ui#208 · Filter by author KlaasHulder opened on Jul 7, 2026
  1

• Idea: Add "state inspector" panel to example for clearer round-trip state visibility

  MCP-UI-Org/mcp-ui#197 · Filter by author blaster151 opened on Apr 18, 2026

• AppRenderer setHostContext effect runs before AppFrame has connected the bridge — Not connected on first mount

  MCP-UI-Org/mcp-ui#195 · Filter by author halfwitgaslit opened on Apr 16, 2026

• AppRenderer sometimes never renders: setup() aborts mid-flight when inline sandbox.url reference changes during iframe load

  MCP-UI-Org/mcp-ui#193 · Filter by author hihiiamjosh opened on Apr 16, 2026

• support Client SDK for Vue

  MCP-UI-Org/mcp-ui#192 · Filter by author 5enxia opened on Apr 13, 2026

• AppFrame sandbox timeout not cleared on effect cleanup — unhandled rejection in React Strict Mode

  MCP-UI-Org/mcp-ui#189 · Filter by author matsjfunke opened on Apr 7, 2026
  3

• feat: Add C# / .NET Server SDK

  MCP-UI-Org/mcp-ui#188 · Filter by author tlewers01 opened on Apr 6, 2026

• sandbox.permissions prop is not respected - hardcoded in setupSandboxProxyIframe

  MCP-UI-Org/mcp-ui#184 · Filter by author kvtemadden opened on Feb 20, 2026

• client SDK: sendSandboxResourceReady missing permissions parameter

  MCP-UI-Org/mcp-ui#180 · Filter by author aharvard opened on Feb 10, 2026
  2

• Multiple message listeners accumulate causing duplicate event handling

  MCP-UI-Org/mcp-ui#177 · Filter by author aharvard opened on Feb 6, 2026
  

• Return text content along with UI

  MCP-UI-Org/mcp-ui#171 · Filter by author dvejsada opened on Jan 9, 2026
  2

• C# Server Sdk support

  MCP-UI-Org/mcp-ui#161 · Filter by author WeihanLi opened on Dec 10, 2025
  1

• Uncaught ReferenceError: process is not defined in ui-resource-renderer.wc.js

  MCP-UI-Org/mcp-ui#160 · Filter by author WorldSecond opened on Dec 9, 2025

• How to support non-HTML-based surfaces?

  MCP-UI-Org/mcp-ui#152 · Filter by author lrosenthol opened on Nov 25, 2025
  1

• The +mcp structured syntax suffix needs to be registered with IANA

  MCP-UI-Org/mcp-ui#151 · Filter by author lrosenthol opened on Nov 25, 2025
  2

• ui:// protocol needs to be registered with IANA

  MCP-UI-Org/mcp-ui#150 · Filter by author lrosenthol opened on Nov 25, 2025

• live demo is not working.

  MCP-UI-Org/mcp-ui#145 · Filter by author ZiqiYe77 opened on Nov 21, 2025
  2

• Python version for Apps SDK

  MCP-UI-Org/mcp-ui#143 · Filter by author mgathena opened on Nov 5, 2025
  1

• MCP-UI Claude Skill

  MCP-UI-Org/mcp-ui#135 · Filter by author dwilbourn-git opened on Oct 22, 2025
  1

• Client SDK layering violation: web-platform layer depends on React

  MCP-UI-Org/mcp-ui#121 · Filter by author EisenbergEffect opened on Oct 8, 2025
  1

• bug: antipattern in web component design

  MCP-UI-Org/mcp-ui#120 · Filter by author EisenbergEffect opened on Oct 8, 2025
  1