File Server/Exception/ToolOutputValidationException.php

1:	<?php
2:
3:	declare(strict_types=1);
4:
5:	/**
6:	* This file is part of the Nexus MCP SDK package.
7:	*
8:	* (c) 2026 John Paul E. Balandan, CPA <paulbalandan@gmail.com>
9:	*
10:	* For the full copyright and license information, please view
11:	* the LICENSE file that was distributed with this source code.
12:	*/
13:
14:	namespace Nexus\Mcp\Server\Exception;
15:
16:	use Nexus\Mcp\Core\Exception\McpExceptionInterface;
17:	use Nexus\Mcp\Server\Validation\SchemaViolation;
18:
19:	/**
20:	* Thrown when a tool's result violates its declared `outputSchema`, by non-conformance or by carrying
21:	* no `structuredContent` at all.
22:	*/
23:	final class ToolOutputValidationException extends \RuntimeException implements McpExceptionInterface
24:	{
25:	/**
26:	* @param list<SchemaViolation> $errors Conformance failures, empty when the result carried no `structuredContent`
27:	*/
28:	public function __construct(string $toolName, array $errors, ?\Throwable $previous = null)
29:	{
30:	parent::__construct(
31:	[] === $errors
32:	? \sprintf('Tool "%s" declares an outputSchema but its result carries no structuredContent.', $toolName)
33:	: \sprintf(
34:	'Tool "%s" returned structuredContent that does not conform to its outputSchema: %s',
35:	$toolName,
36:	implode(' ', array_map(static fn(SchemaViolation $violation): string => $violation->message, $errors)),
37:	),
38:	previous: $previous,
39:	);
40:	}
41:	}
42: