/laravel-ai-sdk

Agent Middleware

Impact: MEDIUM (Intercept and modify prompts before they reach the provider)

Agent middleware intercepts prompts before they are sent to the AI provider. Use middleware for logging, token tracking, prompt modification, or response post-processing.

Bad Example

// Logging scattered inside the agent or controller
class SalesCoach implements Agent
{
    use Promptable;

    public function instructions(): string
    {
        Log::info('SalesCoach prompted'); // Logging in wrong place
        return 'You are a sales coach.';
    }
}

Good Example

// php artisan make:agent-middleware LogPrompts

namespace App\Ai\Middleware;

use Closure;
use Laravel\Ai\Prompts\AgentPrompt;
use Laravel\Ai\Responses\AgentResponse;

class LogPrompts
{
    public function handle(AgentPrompt $prompt, Closure $next)
    {
        Log::info('Prompting agent', ['prompt' => $prompt->prompt]);

        return $next($prompt)->then(function (AgentResponse $response) {
            Log::info('Agent responded', ['text' => $response->text]);
        });
    }
}

// Attach middleware to agent via HasMiddleware interface
use App\Ai\Middleware\LogPrompts;
use Laravel\Ai\Contracts\Agent;
use Laravel\Ai\Contracts\HasMiddleware;
use Laravel\Ai\Promptable;

class SalesCoach implements Agent, HasMiddleware
{
    use Promptable;

    public function instructions(): string
    {
        return 'You are a sales coach.';
    }

    public function middleware(): array
    {
        return [
            new LogPrompts,
        ];
    }
}

Why

• Separation of concerns: Logging, tracking, and modification outside agent logic
• Reusable: Same middleware applied to multiple agents
• Pipeline: Stack multiple middleware for complex requirements
• Post-processing: then() on the response for after-prompt logic

Reference: Laravel AI SDK — Middleware