anthropic-client

name	anthropic-client
description	Integrate Anthropic Claude API with Laravel. HTTP client, message format, error handling. Use when calling Claude models from Laravel applications.

Anthropic Client for Laravel

Call Anthropic Claude APIs from Laravel using native HTTP client.

When to Use

• Claude chat completions (Claude 3.5 Sonnet, Claude 3 Opus)
• Long-context conversations (200K tokens)
• Complex reasoning tasks
• Alternative to OpenAI

---

1. Configuration

Environment Variables

ANTHROPIC_API_KEY=sk-ant-...
ANTHROPIC_BASE_URL=https://api.anthropic.com

Config File

// config/services.php
'anthropic' => [
    'api_key' => env('ANTHROPIC_API_KEY'),
    'base_url' => env('ANTHROPIC_BASE_URL', 'https://api.anthropic.com'),
    'timeout' => 60,
    'version' => '2023-06-01',
],

---

2. Service Class

namespace App\Services;

use Illuminate\Support\Facades\Http;
use Illuminate\Http\Client\PendingRequest;
use Illuminate\Http\Client\Response;

class AnthropicClient
{
    private PendingRequest $http;
    
    public function __construct()
    {
        $this->http = Http::baseUrl(config('services.anthropic.base_url'))
            ->timeout(config('services.anthropic.timeout', 60))
            ->withHeaders([
                'x-api-key' => config('services.anthropic.api_key'),
                'anthropic-version' => config('services.anthropic.version', '2023-06-01'),
                'content-type' => 'application/json',
            ])
            ->retry(3, 100, function ($exception) {
                return $exception instanceof \Illuminate\Http\Client\RequestException
                    && $exception->response?->status() === 429;
            });
    }
    
    /**
     * Create a message (chat completion)
     */
    public function message(
        array $messages,
        string $model = 'claude-3-5-sonnet-20241022',
        int $maxTokens = 4096,
        ?string $system = null,
        float $temperature = 1.0,
    ): array {
        $payload = [
            'model' => $model,
            'max_tokens' => $maxTokens,
            'messages' => $this->formatMessages($messages),
            'temperature' => $temperature,
        ];
        
        if ($system) {
            $payload['system'] = $system;
        }
        
        $response = $this->http->post('/v1/messages', $payload);
        
        $this->handleErrors($response);
        
        return $response->json();
    }
    
    /**
     * Simple prompt helper
     */
    public function prompt(
        string $prompt,
        string $model = 'claude-3-5-sonnet-20241022',
        ?string $systemPrompt = null,
    ): string {
        $messages = [
            ['role' => 'user', 'content' => $prompt],
        ];
        
        $response = $this->message(
            messages: $messages,
            model: $model,
            system: $systemPrompt,
        );
        
        return $response['content'][0]['text'];
    }
    
    /**
     * Format messages for Anthropic API
     * Anthropic requires alternating user/assistant messages
     */
    private function formatMessages(array $messages): array
    {
        $formatted = [];
        
        foreach ($messages as $message) {
            // Skip system messages (handled separately)
            if ($message['role'] === 'system') {
                continue;
            }
            
            $formatted[] = [
                'role' => $message['role'],
                'content' => $message['content'],
            ];
        }
        
        return $formatted;
    }
    
    /**
     * Handle API errors
     */
    private function handleErrors(Response $response): void
    {
        if ($response->successful()) {
            return;
        }
        
        $error = $response->json('error');
        
        match ($response->status()) {
            401 => throw new \Illuminate\Auth\AuthenticationException('Invalid API key'),
            default => throw new \Illuminate\Http\Client\RequestException($response),
        };
    }
}

---

3. Usage Examples

Basic Chat

$claude = app(AnthropicClient::class);

$response = $claude->prompt(
    prompt: 'Explain Laravel queues in 3 sentences.',
    systemPrompt: 'You are a Laravel expert. Be concise.'
);

With Conversation History

$messages = [
    ['role' => 'user', 'content' => 'What is Laravel?'],
    ['role' => 'assistant', 'content' => 'Laravel is a PHP web framework...'],
    ['role' => 'user', 'content' => 'How do I install it?'],
];

$response = $claude->message(
    messages: $messages,
    system: 'You are a helpful Laravel assistant.',
);

$answer = $response['content'][0]['text'];

Long Context

// Claude 3 supports 200K tokens
$longDocument = file_get_contents('large_document.txt');

$response = $claude->prompt(
    prompt: "Summarize this document:\n\n{$longDocument}",
    model: 'claude-3-5-sonnet-20241022',
);

---

4. Models Reference

Model	Context	Speed	Use Case
claude-3-5-sonnet-20241022	200K	Fast	Best balance
claude-3-opus-20240229	200K	Slow	Complex tasks
claude-3-haiku-20240307	200K	Fastest	Simple tasks, cheap

---

5. Key Differences from OpenAI

Feature	OpenAI	Anthropic
Auth header	Authorization: Bearer	x-api-key
System prompt	In messages array	Separate system param
Response format	choices[0].message.content	content[0].text
Max tokens	Optional	Required

---

6. Service Provider

namespace App\Providers;

use App\Services\AnthropicClient;
use Illuminate\Support\ServiceProvider;

class AnthropicServiceProvider extends ServiceProvider
{
    public function register(): void
    {
        $this->app->singleton(AnthropicClient::class, function () {
            return new AnthropicClient();
        });
    }
}

---

Remember: Claude requires max_tokens to be set. System prompts are passed separately, not in the messages array.