bug: ECC breaks Claude Desktop '/' slash menu — getSupportedCommands validation failure

[WilsonLee0714]

Bug Report

Description

When ECC plugin is enabled, Claude Desktop's / slash command menu completely breaks — only built-in commands (schedule, btw, rewind, clear, export) are shown. All custom user skills, plugin skills, and plugin commands disappear.

The root cause is getSupportedCommands validation failure in Desktop's LocalSessions interface.

Error

Repeated in ~/Library/Logs/Claude/claude.ai-web.log:

[REACT_QUERY_CLIENT] QueryClient error: {
  "name": "Error",
  "message": "Error invoking remote method '..._LocalSessions_$_getSupportedCommands': 
  Error: Result from method \"getSupportedCommands\" in interface \"LocalSessions\" failed to pass validation"
}

Environment

• Claude Desktop: 1.2773.0
• Claude Code CLI: 2.1.92
• ECC: v1.9.0 (also tested v1.8.0 — same issue)
• OS: macOS Darwin 25.4.0
• Other plugins working fine: superpowers@5.0.7, codex@1.0.2, chrome-devtools-mcp@0.21.0

Steps to Reproduce

1. Install ECC: claude plugins install everything-claude-code@everything-claude-code
2. Enable ECC in settings
3. Open Claude Desktop, navigate to any project directory
4. Type / in the input box
5. Only built-in commands appear (schedule, btw, rewind, clear, export)
6. Disable ECC → restart Desktop → / menu works again with all skills

Investigation

Systematically isolated via binary testing:

1. Disabled all 4 plugins → / menu works ✅
2. Enabled superpowers only → works ✅
3. Enabled superpowers + codex → works ✅
4. Enabled superpowers + codex + ECC → broken ❌
5. Enabled superpowers + codex + chrome-devtools → works ✅

Additional tests:

• Removed agents field from plugin.json → still broken
• Downgraded to v1.8.0 (no agents/skills/commands fields in plugin.json) → still broken
• Emptied commands/ and skills/ directories → still broken
• Added missing frontmatter to 20 commands + 13 skills that lacked description → still broken

Desktop Logs

When ECC is enabled, Desktop loads the plugin successfully but getSupportedCommands fails validation:

[LocalPluginsReader] Found 4 local plugins
[PluginScan] Skipping legacy command "everything-claude-code:context-budget" — name collides with skills/ entry
[PluginScan] Skipping legacy command "everything-claude-code:rules-distill" — name collides with skills/ entry
[CCD] Passing 6 plugin(s) to SDK (skills: 1, remote: 1, local: 4)

The plugin loads, but the Desktop UI layer fails when it tries to build the / menu from the CLI's command list.

Comparison with Working Plugins

Working plugins (superpowers, codex, chrome-devtools-mcp) have:

• Simple plugin.json without agents/skills/commands fields
• 3-5 commands with clean frontmatter

ECC has:

• 68 commands (20 without frontmatter)
• 150 skills (13 without proper frontmatter)
• plugin.json with agents, skills, commands fields

Workaround

Disable ECC in Desktop (enabledPlugins: false). ECC skills still work in CLI.

Related

• bug(plugin): "agents" field in plugin.json fails manifest validation — plugin fails to install #1459 — agents field in plugin.json fails manifest validation (related but not the full fix)
• Commands not registered after migration from plugin.json to agent.yaml #1327 — Commands not registered after migration from plugin.json to agent.yaml

Expected Behavior

ECC should not break Desktop's / menu. Either:

1. Fix command/skill metadata to pass Desktop's getSupportedCommands validation schema
2. Or gracefully degrade (skip invalid entries instead of failing the entire list)