[BUG] Desktop Code: marketplace MCPB plugin has no UI to configure required credentials

What's wrong?

In Claude Desktop's Code tab, a marketplace plugin with required Redis connection settings installs successfully, but no credential form appears at install time or when the plugin is enabled. The installed connector detail screen displays command, arguments, and masked environment variables as read-only. There is no Configure or Edit action to enter the Redis URL, store ID, or API key.

This is a current Desktop reproduction related to #89749 and #95683. I found those reports while investigating and am linking them rather than claiming this symptom is new. Please consolidate with the canonical issue if appropriate.

Environment

• Claude Desktop: 2.42304.0
• macOS: 26.7.1
• Surface: Claude Desktop → Code → This computer
• Separately installed diagnostic CLI: 2.1.301 (Claude Code). This is not a claim that the Desktop app embeds that exact CLI build.
• Plugin: Redis Agent Memory 0.1.2
• Regression status: unknown; no working Desktop UI version verified.

Steps to reproduce

1. In Claude Desktop, open Customize → Plugins → Add marketplace.
2. Add https://github.com/alberttwong/redis-agent-memory-mcp and install Redis Agent Memory. The observed plugin revision is linked below because the repository is continuing to evolve.
3. Enable plugin v0.1.2 and start a fresh local Code session.
4. Observe that no Redis URL, store ID, or API key prompt appears.
5. Open the installed plugin's Connectors → redis-agent-memory details.
6. Observe that command, arguments, and environment variables are only displayed, with no credential editing controls. The plugin's More options menu only offered Show in Finder and Remove.

Reproduction source:

• Plugin v0.1.2 manifest
• Referenced MCPB manifest

The plugin uses an HTTPS MCPB reference:

{
  "mcpServers": "https://github.com/alberttwong/redis-agent-memory-mcp/releases/download/v0.1.1/redis-agent-memory-0.1.1.mcpb",
  "userConfig": {
    "base_url": {
      "type": "string",
      "title": "Redis Agent Memory URL",
      "description": "HTTPS base URL for the Redis Agent Memory service.",
      "required": true
    },
    "store_id": {
      "type": "string",
      "title": "Store ID",
      "description": "Redis Agent Memory store identifier.",
      "required": true
    },
    "api_key": {
      "type": "string",
      "title": "Store API key",
      "description": "API key for the selected Redis Agent Memory store.",
      "sensitive": true,
      "required": true
    }
  }
}

The MCPB itself also declares the corresponding user_config fields and references them in its server environment. Adding the top-level plugin fields did not surface an input dialog in Desktop. Both marketplace and plugin passed claude plugin validate --strict; validation alone did not establish a working configuration flow.

Expected behavior

Provide a Desktop configuration form for required plugin/bundle fields during installation or enabling, and a way to reopen it later. Mask the API key, but distinguish missing credentials from configured values.

If this plugin/bundle configuration mechanism is unsupported on Desktop, show that limitation explicitly rather than presenting an enabled plugin with unconfigurable settings. In particular, clarify the distinction between plugin-level userConfig storage and MCPB-level user_config storage described in #95683.

Actual result and impact

The connector panel shows these names with masked values and no editing controls:

AGENT_MEMORY_BASE_URL
AGENT_MEMORY_STORE_ID
AGENT_MEMORY_API_KEY
AGENT_MEMORY_OWNER_ID
AGENT_MEMORY_NAMESPACE_ID
AGENT_MEMORY_NAMESPACE
AGENT_MEMORY_AGENT_ID

The session's MCP server list did not include Redis Agent Memory. Asking for memory_health produced a response stating that the session had no such tool. I am reporting these as observed symptoms, not asserting that the missing dialog alone proves every cause of the server-loading failure.

The user cannot complete a GUI-only setup or verify the Redis connection. No real API keys, account identifiers, or private logs are included here.

Related reports and documentation

• #89749: no plugin userConfig collection/configuration UI on Desktop and VS Code.
• #95683: MCPB user_config is not prompted for; plugin option storage and bundle configuration storage differ.
• #100926: plugin configuration rows missing until plugin reload in Desktop-hosted sessions.
• https://code.claude.com/docs/en/plugins-reference#user-configuration

A separately implemented local browser setup form is being tested as an application workaround; this report concerns the missing native Desktop credential configuration flow.