Do block classes (not components) need to be registered somehow?

[stuartmcgill]

I'm following the documentation on Validating blocks and would like to do some custom validation beyond what's available in the Blade templates.

My blocks are Blade templates, which I understand I can supplement with block classes as long as they're in the App\Twill\Block namespace. For now I'm just trying to get my new block service (in /app/Twill/Block) to be called by Twill:

<?php

declare(strict_types=1);

namespace App\Twill\Block;

use A17\Twill\Services\Blocks\Block;

class Videolink extends Block
{
    public $rules = [
        'name' => 'required',
        'embeddedText' => 'required',
    ];
}

Is there something else I need to do? My block is not being invoked (stepping through the code I can see that for videolink blocks the standard Block service is used instead).

After inspecting the Twill code I tried adding some config in case this was a missing step in the documentation, but that just led to this error about a missing title (although there is one in the Blade file).

'block_editor' => [
        'directories' => [
            'source' => [
                'blocks' => [
                    [
                        'path' => base_path('/app/Twill/Block'),
                        'source' => A17\Twill\Services\Blocks\Block::SOURCE_APP,
                    ],
                ],
                'repeaters' => [],
            ]
        ],
        'use_twill_blocks' => [],

The Blade template is:

@twillBlockTitle('Video link')
@twillBlockIcon('video')
@twillBlockGroup('app')
{{--@twillBlockValidationRules([--}}
{{--    'name' => 'required',--}}
{{--    'embeddedText' => 'required',--}}
{{--])--}}

<x-twill::input
    name="name"
    label="Name"
    :required="true"
    note="For internal use only"
/>

<x-twill::input
    name="embeddedText"
    label="Link to video"
    :required="true"
    type="text"
    placeholder="Copy the embedded video HTML here"
/>

Thank you in advance for any guidance as to what I'm doing wrong.

[stuartmcgill]

In the end I used a block component and this was easy to get working - I'd still be interested to find out what I was missing, but it's more of an academic question now as I think I'll use components from now on.