Events

Name: Events & Listeners Description: Decoupled communication between application layers. Events are plain data objects describing what happened; listeners react to those events with a single, specific side effect. Compatible Agents: general-purpose, backend Tags: app/Events//*.php, app/Listeners//*.php, laravel, php, backend, event, listener, observer-pattern

Rules

• Event classes live in app/Events/; listener classes live in app/Listeners/
• Events are plain data containers — no logic inside events
• Listeners handle one specific reaction each — never bundle multiple side effects
• Events: past-tense noun phrase → InvoicePaid, UserRegistered, OrderShipped
• Listeners: verb phrase describing the reaction → SendInvoicePaidNotification, UpdateInventory
• Dispatch events from inside an Action after the operation completes — never from a controller or model directly
• Register events and listeners in EventServiceProvider
• Implement ShouldQueue on listeners for side effects that can be deferred
• Define a failed() method on queued listeners
• Use events when one action triggers multiple independent side effects

Examples

// Event — data container only
namespace App\Events;

use App\Models\Invoice;
use Illuminate\Foundation\Events\Dispatchable;
use Illuminate\Queue\SerializesModels;

class InvoicePaid
{
    use Dispatchable, SerializesModels;

    public function __construct(
        public readonly Invoice $invoice,
    ) {}
}

// Listener — one reaction
namespace App\Listeners;

use App\Events\InvoicePaid;
use App\Notifications\InvoicePaidNotification;
use Illuminate\Contracts\Queue\ShouldQueue;

class SendInvoicePaidNotification implements ShouldQueue
{
    public function handle(InvoicePaid $event): void
    {
        $event->invoice->user->notify(new InvoicePaidNotification($event->invoice));
    }

    public function failed(InvoicePaid $event, \Throwable $exception): void
    {
        // Handle failure
    }
}

// Dispatching — from inside an Action
class MarkInvoiceAsPaid
{
    public function execute(Invoice $invoice): void
    {
        $invoice->update(['paid_at' => now()]);
        InvoicePaid::dispatch($invoice);
    }
}

// Registration — one event, many listeners
protected $listen = [
    InvoicePaid::class => [
        SendInvoicePaidNotification::class,
        UpdateAccountingRecords::class,
        NotifyAccountManager::class,
    ],
];

Anti-Patterns

• Adding business logic inside an Event class
• Bundling multiple reactions in a single Listener (one listener, one reaction)
• Dispatching events from controllers or models directly — dispatch from Actions
• Using events for simple, single side effects that can be triggered directly
• Not implementing failed() on queued listeners for critical side effects
• Creating event chains that obscure control flow and make debugging hard

References

• Laravel Events
• Related: Actions/SKILL.md — events should be dispatched from Actions
• Related: Observers/SKILL.md — for model lifecycle reactions