# Claude API — PHP > **Note:** The PHP SDK is the official Anthropic SDK for PHP. Tool runner and Agent SDK are not available. Bedrock, Vertex AI, and Foundry clients are supported. ## Installation ```bash composer require "anthropic-ai/sdk" ``` ## Client Initialization ```php use Anthropic\Client; // Using API key from environment variable $client = new Client(apiKey: getenv("ANTHROPIC_API_KEY")); ``` ### Amazon Bedrock ```php use Anthropic\BedrockClient; $client = new BedrockClient( region: 'us-east-1', ); ``` ### Google Vertex AI ```php use Anthropic\VertexClient; $client = new VertexClient( region: 'us-east5', projectId: 'my-project-id', ); ``` ### Anthropic Foundry ```php use Anthropic\FoundryClient; $client = new FoundryClient( authToken: getenv("ANTHROPIC_AUTH_TOKEN"), ); ``` --- ## Basic Message Request ```php $message = $client->messages->create( model: 'claude-opus-4-6', maxTokens: 1024, messages: [ ['role' => 'user', 'content' => 'What is the capital of France?'], ], ); echo $message->content[0]->text; ``` --- ## Streaming ```php $stream = $client->messages->createStream( model: 'claude-opus-4-6', maxTokens: 1024, messages: [ ['role' => 'user', 'content' => 'Write a haiku'], ], ); foreach ($stream as $event) { echo $event; } ``` --- ## Tool Use (Manual Loop) The PHP SDK supports raw tool definitions via JSON schema. See the [shared tool use concepts](../shared/tool-use-concepts.md) for the tool definition format and agentic loop pattern.