Extension UI (VSCode)

This chapter covers VSCode-specific UI for managing extensions. For general extension concepts, see Agent Extensions.

Configuration Storage

Extensions are configured via the symposium.extensions VS Code setting:

"symposium.extensions": [
  { "id": "sparkle", "_enabled": true, "_source": "built-in" },
  { "id": "ferris", "_enabled": true, "_source": "built-in" },
  { "id": "cargo", "_enabled": true, "_source": "built-in" }
]

Custom extensions include their distribution:

{
  "id": "my-extension",
  "_enabled": true,
  "_source": "custom",
  "name": "My Extension",
  "distribution": {
    "npx": { "package": "@myorg/my-extension" }
  }
}

Default behavior - when no setting exists, all built-in extensions are enabled. If the user returns to the default configuration, the key is removed from settings.json entirely.

Settings UI

The Settings panel includes an Extensions section where users can:

• Enable/disable extensions via checkbox
• Reorder extensions by dragging the handle
• Delete extensions from the list
• Add extensions via the “+ Add extension” link, which opens a QuickPick dialog

Add Extension Dialog

The QuickPick dialog shows three sections:

1. Built-in - sparkle, ferris, cargo (greyed out if already added)
2. From Registry - extensions from the shared registry with type: "extension"
3. Add Custom Extension:
   • From executable on your system (local command/path)
   • From npx package
   • From pipx package
   • From cargo crate
   • From URL to extension.json (GitHub URLs auto-converted to raw)

Spawn Integration

When spawning an agent, the extension builds --proxy arguments from enabled extensions:

symposium-acp-agent run-with --proxy sparkle --proxy ferris --proxy cargo --agent '...'

Only enabled extensions are passed, in their configured order.