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Overview

Instructor uses validation to verify if the response generated by LLM meets the requirements of your response model. If the response does not meet the requirements, Instructor will throw an exception.

Instructor uses Symfony’s Validator component to validate the response, check their documentation for more information on the usage: https://symfony.com/doc/current/components/validator.html

Following example demonstrates how to use Symfony Validator’s constraints to validate the email field of response.

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Example

<?php
$loader = require 'vendor/autoload.php';
$loader->add('Cognesy\\Instructor\\', __DIR__.'../../src/');

use Cognesy\Instructor\Instructor;
use Symfony\Component\Validator\Constraints as Assert;

class UserDetails
{
    public string $name;
    #[Assert\Email]
    #[Assert\NotBlank]
    /** Find user's email provided in the text */
    public string $email;
}

$caughtException = false;
$user = (new Instructor)->request(
    messages: [['role' => 'user', 'content' => "you can reply to me via mail -- Jason"]],
    responseModel: UserDetails::class,
)->onError(function($e) use (&$caughtException) {
    $caughtException = true;
})->get();


dump($user);

assert($user === null);
assert($caughtException === true);
?>
Using LLM API connections from config fileValidation across multiple fields