A Laravel chat controller in PHP using AWS Bedrock API

ChatController.php

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use Illuminate\Support\Facades\Http;
use Aws\BedrockRuntime\BedrockRuntimeClient;

class ChatController extends Controller
{

    protected $instruction = <<<EOD
    [INST]You are now chatting with a friendly assistant! Feel free to ask any questions or share your thoughts. [/INST]
    EOD;

    protected $client = null;

    public function __construct() {
        // Constructor method, called when a new instance is created
        $this->client = new BedrockRuntimeClient([
            'version' => 'latest',
            'region' => 'us-east-1'
        ]);
    }
    
    public function getChatResponse(Request $request)
    {
        // Method to handle chatbot requests
        $input = $request->input('input');
        $formattedPrompt = sprintf("%s\n%s\n", $this->instruction, $input);
        $session = $request->input('session');
        $response = $this->client->invokeModel([
            'modelId' => 'meta.llama2-13b-chat-v1',
            'body' => json_encode([
                'prompt' => $formattedPrompt,
                'max_gen_len' => 128,
                'temperature' => 0.1,
                'top_p' => 0.9
            ]),
            'accept' => 'application/json',
            'contentType' => 'application/json'
        ]);
        $output = json_decode($response['body'], true)['generation'];
        return response()->json(['output' => $output, 'session' => $session]);
    }
}