Constant WIDGET_LIST_TOOL 

pub(crate) const WIDGET_LIST_TOOL: &str = r#"{
  "name": "WidgetList",
  "description": "List the AgentMux widgets installed on this machine: id, name, version, kind (sandboxed or trusted), state (approved, needs_approval, changed, invalid with its error, disabled), permissions, folder and the views it adds. Use it to see whether a widget you built installed, and what view to pass to OpenWidget.",
  "inputSchema": { "type": "object", "properties": {} }
}"#;