Anthropic

Configuration

'anthropic' => [
    'api_key' => env('ANTHROPIC_API_KEY', ''),
    'version' => env('ANTHROPIC_API_VERSION', '2023-06-01'),
]

Prompt caching

Anthropic's prompt caching feature allows you to drastically reduce latency and your API bill when repeatedly re-using blocks of content within five minutes of each other.

We support Anthropic prompt caching on:

• System Messages (text only)
• User Messages (Text, Image and PDF (pdf only))
• Assistant Messages (text only)
• Tools

The API for enabling prompt caching is the same for all, enabled via the withProviderMeta() method. Where a UserMessage contains both text and an image or document, both will be cached.

use EchoLabs\Enums\Provider;
use EchoLabs\Prism\Prism;
use EchoLabs\Prism\Tool;
use EchoLabs\Prism\ValueObjects\Messages\UserMessage;
use EchoLabs\Prism\ValueObjects\Messages\SystemMessage;

Prism::text()
    ->using(Provider::Anthropic, 'claude-3-5-sonnet-20241022')
    ->withMessages([
        (new SystemMessage('I am a long re-usable system message.'))
            ->withProviderMeta(Provider::Anthropic, ['cacheType' => 'ephemeral']),

        (new UserMessage('I am a long re-usable user message.'))
            ->withProviderMeta(Provider::Anthropic, ['cacheType' => 'ephemeral'])
    ])
    ->withTools([
        Tool::as('cache me')
            ->withProviderMeta(Provider::Anthropic, ['cacheType' => 'ephemeral'])
    ])
    ->generate();

If you prefer, you can use the AnthropicCacheType Enum like so:

use EchoLabs\Enums\Provider;
use EchoLabs\Prism\Providers\Anthropic\Enums\AnthropicCacheType;
use EchoLabs\Prism\ValueObjects\Messages\UserMessage;
use EchoLabs\Prism\ValueObjects\Messages\Support\Document;

(new UserMessage('I am a long re-usable user message.'))->withProviderMeta(Provider::Anthropic, ['cacheType' => AnthropicCacheType::ephemeral])

Note that you must use the withMessages() method in order to enable prompt caching, rather than withPrompt() or withSystemPrompt().

Please ensure you read Anthropic's prompt caching documentation, which covers some important information on e.g. minimum cacheable tokens and message order consistency.

Documents

PDF Documents

Prism supports Anthropic PDF processing on UserMessages via the $additionalContent parameter:

use EchoLabs\Enums\Provider;
use EchoLabs\Prism\Prism;
use EchoLabs\Prism\ValueObjects\Messages\UserMessage;
use EchoLabs\Prism\ValueObjects\Messages\Support\Document;

Prism::text()
    ->using(Provider::Anthropic, 'claude-3-5-sonnet-20241022')
    ->withMessages([
        new UserMessage('Here is the document from base64', [
            Document::fromBase64(base64_encode(file_get_contents('tests/Fixtures/test-pdf.pdf')), 'application/pdf'),
        ]),
        new UserMessage('Here is the document from a local path', [
            Document::fromPath('tests/Fixtures/test-pdf.pdf'),
        ]),
    ])
    ->generate();

Anthropic use vision to process PDFs, and consequently there are some limitations detailed in their feature documentation.

Txt and md Documents

Prism supports txt/md documents on UserMessages via the $additionalContent parameter:

use EchoLabs\Enums\Provider;
use EchoLabs\Prism\Prism;
use EchoLabs\Prism\ValueObjects\Messages\UserMessage;
use EchoLabs\Prism\ValueObjects\Messages\Support\Document;

Prism::text()
    ->using(Provider::Anthropic, 'claude-3-5-sonnet-20241022')
    ->withMessages([
        new UserMessage('Here is the document from a text string (e.g. from your database)', [
            Document::fromText('Hello world!'),
        ]),
        new UserMessage('Here is the document from a local path', [
            Document::fromPath('tests/Fixtures/test-txt.txt'),
        ]),
    ])
    ->generate();

Custom content documents

Prism supports Anthropic's "custom content documents", which is primarily for use with citations (see below) where you need citations to reference your own chunking strategy.

use EchoLabs\Enums\Provider;
use EchoLabs\Prism\Prism;
use EchoLabs\Prism\ValueObjects\Messages\UserMessage;
use EchoLabs\Prism\ValueObjects\Messages\Support\Document;

Prism::text()
    ->using(Provider::Anthropic, 'claude-3-5-sonnet-20241022')
    ->withMessages([
        new UserMessage(
            content: "Is the grass green and the sky blue?",
            additionalContent: [
                Document::fromChunks(["The grass is green.", "Flamingos are pink.", "The sky is blue."])
            ]
        )
    ])
    ->generate();

Citations

Prism supports Anthropic's citations feature for both text and structured.

Please note however that due to Anthropic not supporting "native" structured output, and Prism's workaround for this, the output can be unreliable. You should therefore ensure you implement proper error handling for the scenario where Anthropic does not return a valid decodable schema.

Enabling citations

Anthropic require citations to be enabled on all documents in a request. To enable them, using the withProviderMeta() method when building your request:

use EchoLabs\Enums\Provider;
use EchoLabs\Prism\Prism;
use EchoLabs\Prism\ValueObjects\Messages\UserMessage;
use EchoLabs\Prism\ValueObjects\Messages\Support\Document;

$response = Prism::text()
    ->using(Provider::Anthropic, 'claude-3-5-sonnet-20241022')
    ->withMessages([
        new UserMessage(
            content: "Is the grass green and the sky blue?",
            additionalContent: [
                Document::fromChunks(
                    chunks: ["The grass is green.", "Flamingos are pink.", "The sky is blue."],
                    title: 'The colours of nature',
                    context: 'The go-to textbook on the colours found in nature!'
                )
            ]
        )
    ])
    ->withProviderMeta(Provider::Anthropic, ['citations' => true])
    ->generate();

Accessing citations

You can access the chunked output with its citations via the additionalContent property on a response, which returns an array of Providers\Anthropic\ValueObjects\MessagePartWithCitationss.

As a rough worked example, let's assume you want to implement footnotes. You'll need to loop through those chunks and (1) re-construct the message with links to the footnotes; and (2) build an array of footnotes to loop through in your frontend.

use EchoLabs\Prism\Providers\Anthropic\ValueObjects\MessagePartWithCitations;
use EchoLabs\Prism\Providers\Anthropic\ValueObjects\Citation;

$messageChunks = $response->additionalContent['messagePartsWithCitations'];

$text = '';
$footnotes = '';

$footnoteId = 1;

/** @var MessagePartWithCitations $messageChunk  */
foreach ($messageChunks as $messageChunk) {
    $text .= $messageChunk->text;
    
    /** @var Citation $citation */
    foreach ($messageChunk->citations as $citation) {
        $footnotes[] = [
            'id' => $footnoteId,
            'document_title' => $citation->documentTitle,
            'reference_start' => $citation->startIndex,
            'reference_end' => $citation->endIndex
        ];
    
        $text .= '<sup><a href="#footnote-'.$footnoteId.'">'.$footnoteId.'</a></sup>';
    
        $footnoteId++;
    }
}

Considerations

Message Order

• Message order matters. Anthropic is strict about the message order being:

1. UserMessage
2. AssistantMessage
3. UserMessage

Structured Output

While Anthropic models don't have native JSON mode or structured output like some providers, Prism implements a robust workaround for structured output:

• We automatically append instructions to your prompt that guide the model to output valid JSON matching your schema
• If the response isn't valid JSON, Prism will raise a PrismException

Limitations

Messages

Most providers' API include system messages in the messages array with a "system" role. Anthropic does not support the system role, and instead has a "system" property, separate from messages.

Therefore, for Anthropic we:

• Filter all SystemMessages out, omitting them from messages.
• Always submit the prompt defined with ->withSystemPrompt() at the top of the system prompts array.
• Move all SystemMessages to the system prompts array in the order they were declared.

Images

Does not support Image::fromURL