Kick off the SDK based on Symfony's MCP SDK

src/Capability/PromptChain.php

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+<?php
+
+/*
+ * This file is part of the official PHP MCP SDK.
+ *
+ * A collaboration between Symfony and the PHP Foundation.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Mcp\Capability;
+
+use Mcp\Capability\Prompt\CollectionInterface;
+use Mcp\Capability\Prompt\IdentifierInterface;
+use Mcp\Capability\Prompt\MetadataInterface;
+use Mcp\Capability\Prompt\PromptGet;
+use Mcp\Capability\Prompt\PromptGetResult;
+use Mcp\Capability\Prompt\PromptGetterInterface;
+use Mcp\Exception\InvalidCursorException;
+use Mcp\Exception\PromptGetException;
+use Mcp\Exception\PromptNotFoundException;
+
+/**
+ * A collection of prompts. All prompts need to implement IdentifierInterface.
+ *
+ * @author Tobias Nyholm <tobias.nyholm@gmail.com>
+ */
+class PromptChain implements PromptGetterInterface, CollectionInterface
+{
+    public function __construct(
+        /**
+         * @var IdentifierInterface[]
+         */
+        private readonly array $items,
+    ) {
+    }
+
+    public function getMetadata(int $count, ?string $lastIdentifier = null): iterable
+    {
+        $found = null === $lastIdentifier;
+        foreach ($this->items as $item) {
+            if (!$item instanceof MetadataInterface) {
+                continue;
+            }
+
+            if (false === $found) {
+                $found = $item->getName() === $lastIdentifier;
+                continue;
+            }
+
+            yield $item;
+            if (--$count <= 0) {
+                break;
+            }
+        }
+
+        if (!$found) {
+            throw new InvalidCursorException($lastIdentifier);
+        }
+    }
+
+    public function get(PromptGet $input): PromptGetResult
+    {
+        foreach ($this->items as $item) {
+            if ($item instanceof PromptGetterInterface && $input->name === $item->getName()) {
+                try {
+                    return $item->get($input);
+                } catch (\Throwable $e) {
+                    throw new PromptGetException($input, $e);
+                }
+            }
+        }
+
+        throw new PromptNotFoundException($input);
+    }
+}