> ## Documentation Index
> Fetch the complete documentation index at: https://docs.instructorphp.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Decision runtime

## Overview

Use the explicit runtime when application code owns configuration and request
lifecycle. Creating a pending decision is lazy; consuming it executes once and
memoizes the typed response.

## Example

```php theme={null}
<?php
require 'examples/boot.php';

use Cognesy\Polyglot\Decision\Collections\Questions;
use Cognesy\Polyglot\Decision\Config\DecisionConfig;
use Cognesy\Polyglot\Decision\Config\DecisionRetryPolicy;
use Cognesy\Polyglot\Decision\Data\DecisionRequest;
use Cognesy\Polyglot\Decision\DecisionRuntime;
use Cognesy\Polyglot\Decision\Questions\Noul;

$runtime = DecisionRuntime::fromConfig(
    DecisionConfig::fromPreset('typesafe'),
);

$request = new DecisionRequest(
    input: 'Our checkout API has returned 503 for every request since 09:10 UTC.',
    questions: Questions::of(new Noul(
        id: 'production_incident',
        instructions: 'Does this message describe an active production incident?',
    )),
    retryPolicy: new DecisionRetryPolicy(
        maxAttempts: 3,
        baseDelayMs: 250,
        maxDelayMs: 2000,
    ),
);

$pending = $runtime->create($request);

echo "Request ID: {$pending->request()->id()->toString()}\n";
echo "Execution ID: {$pending->executionId()}\n";

$response = $pending->response();
$sameResponse = $pending->response();
$incident = $response->answers()->noul('production_incident');

echo "Model: {$response->model()}\n";
echo 'Incident probability: '.number_format($incident->probability(), 2)."\n";
echo 'Usage: '.json_encode(
    $response->usage()->toArray(),
    JSON_THROW_ON_ERROR,
)."\n";

assert($response === $sameResponse);
assert($incident->probability() >= 0.0 && $incident->probability() <= 1.0);
assert(DecisionRequest::fromArray($request->toArray())->toArray() === $request->toArray());
?>
```