io.input.boolean() asks a yes or no question and returns true or false. Provided by the @awaitio/input-boolean package.

Install
Setup
Register it under the key you want inio, see Input components:
app.ts
Usage
Props
Returns
boolean: true when the box is checked, false when it is not.
Built-in validation
Nothing is checked: an unchecked box givesfalse.
Custom validation
Chain.validate() for a check of your own. It runs on the server after the checks above, gets the value the handler would get and returns a message to show under the field, or nothing when the value is fine; see Custom validation.