View not rendering in Claude Desktop

[fredericbarthelet]

Same here. Registered a Skybridge (v1.2.5) server with Claude Desktop, both via a stdio wrapper (mcp-remote → local HTTP) and via direct HTTP transport — same result both ways.

• tools/call succeeds and returns correct structuredContent.
• resources/list returns the tool's ui://views/ext-apps/<name>.html resource correctly.
• resources/read on that URI returns valid text/html;profile=mcp-app content, which correctly references a reachable JS bundle (verified 200 OK, correct CORS/content-type headers) served from the same local server.

Despite all of this checking out manually via curl, Claude Desktop renders the tool's plain-text result instead of the interactive view — no widget, no error, just text.

One thing that stood out: tools/list's per-tool _meta is shaped as:

"_meta": {
  "ui/resourceUri": "ui://views/...",
  "ui": { "resourceUri": "ui://views/..." }
}

Is this the _meta shape Claude Desktop's current MCP Apps client actually expects? Wondering if there's a mismatch between how Skybridge advertises the UI resource and what Desktop's client looks for.

Happy to share full request/response logs if useful.

Originally posted by @n-sviridenko in #891

[fredericbarthelet]

@n-sviridenko did you deploy your MCP App by any chance. That'd be great to have a URL we can use to reproduce your bug.
ui/resourceUri in meta is a backward compatible field for old clients that used that specs. ui.resourceUri is the updated entrypoint from MCP App spec.

[n-sviridenko]

@fredericbarthelet thanks for a quick response. seems like its a global issue for any mcp app when using Claude Desktop (also tried w/ some dummy @modelcontextprotocol examples they had)

anthropics/claude-ai-mcp#61
anthropics/claude-ai-mcp#165

do mcp apps work on your end when using claude desktop btw?