diff --git a/src/Integrations/WordPress/Status/PostCloner.php b/src/Integrations/WordPress/Status/PostCloner.php
index 3b350a7..6c62d7d 100644
--- a/src/Integrations/WordPress/Status/PostCloner.php
+++ b/src/Integrations/WordPress/Status/PostCloner.php
@@ -11,10 +11,12 @@ use WP_Error;
 use WP_Post;
 
 /**
- * Copies entries (draft copy) and swaps a copy's content back into its original.
- * Meta is copied raw – Divi flags (_et_pb_*), page template (_wp_page_template),
- * featured image (_thumbnail_id) and Pods meta included; Pods relationships stored in
- * the meta table travel with it. Only per-post bookkeeping (SKIP_META) stays put.
+ * Copies entries (draft copy, trashed backup) and swaps a copy's content back into its
+ * original. Meta is copied byte-exact: the stored meta_value strings are read and
+ * inserted directly via $wpdb, so nothing is unserialized, re-serialized or unslashed on
+ * the way – Divi flags (_et_pb_*), page template (_wp_page_template), featured image
+ * (_thumbnail_id) and Pods meta included; Pods relationships stored in the meta table
+ * travel with it. Only per-post bookkeeping (SKIP_META) stays put.
  * snapshot()/restore() let lit/post-replace-with-copy undo a failed swap.
  * Not final so abilities can be tested with a mock.
  */
@@ -22,15 +24,25 @@ class PostCloner
 {
     public const COPY_OF_META = '_lit_mcp_copy_of';
 
+    public const BACKUP_OF_META = '_lit_mcp_backup_of';
+
     public const COPY_SUFFIX = ' (Kopie)';
 
+    public const BACKUP_SUFFIX = ' (Sicherung)';
+
+    /** Parts of a post replace()/restore() write. */
+    public const PARTS = ['post', 'meta', 'terms'];
+
     /** Bookkeeping meta that belongs to one post and must never be copied or cleared. */
     private const SKIP_META = [
         '_edit_lock', '_edit_last', '_wp_old_slug', '_wp_old_date', '_wp_trash_meta_status',
         '_wp_trash_meta_time', '_wp_desired_post_slug', '_encloseme', '_pingme', self::COPY_OF_META,
+        self::BACKUP_OF_META,
     ];
 
-    private const DUPLICATE_REASON = 'Die Kopie konnte nicht vollständig angelegt werden.';
+    public function __construct(private ?\wpdb $db = null)
+    {
+    }
 
     /**
      * Creates "<title> (Kopie)" as draft of the current user. All or nothing: if meta or
@@ -40,75 +52,63 @@ class PostCloner
      */
     public function duplicate(WP_Post $original): int
     {
-        $originalId = (int) $original->ID;
-        $copyId = wp_insert_post(wp_slash([
-            'post_type' => (string) $original->post_type,
-            'post_status' => 'draft',
-            'post_title' => (string) $original->post_title . self::COPY_SUFFIX,
-            'post_content' => (string) $original->post_content,
-            'post_excerpt' => (string) $original->post_excerpt,
-            'post_parent' => (int) $original->post_parent,
-            'menu_order' => (int) $original->menu_order,
-            'comment_status' => (string) $original->comment_status,
-            'ping_status' => (string) $original->ping_status,
-            'post_password' => (string) $original->post_password,
-            'post_author' => get_current_user_id(),
-        ]), true);
+        return $this->cloneAsDraft($original, self::COPY_SUFFIX, self::COPY_OF_META, 'Die Kopie');
+    }
 
-        if ($copyId instanceof WP_Error || (int) $copyId === 0) {
-            $reason = $copyId instanceof WP_Error ? $copyId->get_error_message() : 'unknown error';
-            throw new WriteFailed(
-                'Die Kopie konnte nicht angelegt werden.',
-                true,
-                null,
-                null,
-                null,
-                sprintf('Copy of post %d could not be created: %s', $originalId, $reason)
-            );
-        }
+    /**
+     * Creates "<title> (Sicherung)" – a full clone of the post – and moves it to the trash.
+     * If either step fails, the backup is deleted again. Call only when the trash is enabled.
+     *
+     * @throws WriteFailed
+     */
+    public function backup(WP_Post $original): int
+    {
+        $backupId = $this->cloneAsDraft($original, self::BACKUP_SUFFIX, self::BACKUP_OF_META, 'Die Sicherung');
 
-        $copyId = (int) $copyId;
         try {
-            $this->replaceMeta($copyId, $this->ownMeta($originalId));
-            $this->setTerms($copyId, $this->termIds($original));
-            if (update_post_meta($copyId, self::COPY_OF_META, $originalId) === false) {
-                throw new RuntimeException('Copy marker could not be written.');
+            $trashed = wp_trash_post($backupId);
+            if (! $trashed || get_post_status($backupId) !== 'trash') {
+                throw new RuntimeException('Backup could not be moved to the trash.');
             }
         } catch (Throwable $e) {
-            $deleted = wp_delete_post($copyId, true);
-            $detail = sprintf('Copy %d of post %d failed: %s', $copyId, $originalId, $e->getMessage());
-            if ($deleted) {
-                throw new WriteFailed(self::DUPLICATE_REASON, true, null, null, $e, $detail . '; draft deleted');
-            }
-
-            throw new WriteFailed(self::DUPLICATE_REASON, false, $copyId, null, $e, $detail);
+            $this->discard($original, $backupId, $e, 'Die Sicherung konnte nicht in den Papierkorb gelegt werden.');
         }
 
-        return $copyId;
+        return $backupId;
     }
 
     /**
      * Writes title (without " (Kopie)"), content, excerpt, meta and terms of the copy
      * into the original. Status, slug, date and author of the original stay.
      *
-     * @throws RuntimeException
+     * @throws ReplaceFailed Naming the parts that were (possibly) written.
      */
     public function replace(WP_Post $original, WP_Post $copy): void
     {
         $originalId = (int) $original->ID;
-        $this->updateRow($originalId, [
-            'post_title' => self::withoutSuffix((string) $copy->post_title),
-            'post_content' => (string) $copy->post_content,
-            'post_excerpt' => (string) $copy->post_excerpt,
-        ]);
-        $this->replaceMeta($originalId, $this->ownMeta((int) $copy->ID));
-        $this->setTerms($originalId, $this->termIds($copy));
+        $parts = [];
+        try {
+            $parts[] = 'post';
+            $this->updateRow($originalId, [
+                'post_title' => self::withoutSuffix((string) $copy->post_title),
+                'post_content' => (string) $copy->post_content,
+                'post_excerpt' => (string) $copy->post_excerpt,
+            ]);
+            $meta = $this->ownMeta((int) $copy->ID);
+            $terms = $this->termIds($copy);
+            $parts[] = 'meta';
+            $this->replaceMeta($originalId, $meta);
+            $parts[] = 'terms';
+            $this->setTerms($originalId, $terms);
+        } catch (Throwable $e) {
+            throw new ReplaceFailed($parts, $e);
+        }
     }
 
     /**
      * Everything replace() overwrites – call before replace().
      *
-     * @return array{post: array<string, string>, meta: array<string, list<mixed>>, terms: array<string, list<int>>}
+     * @return array{post: array<string, string>, meta: array<string, list<?string>>, terms: array<string, list<int>>}
      * @throws RuntimeException
      */
     public function snapshot(WP_Post $post): array
@@ -125,22 +125,23 @@ class PostCloner
     }
 
     /**
-     * Writes a snapshot back. Tries every part even if one fails.
+     * Writes the given parts of a snapshot back. Tries every part even if one fails.
      *
-     * @param array{post: array<string, string>, meta: array<string, list<mixed>>, terms: array<string, list<int>>}
+     * @param array{post: array<string, string>, meta: array<string, list<?string>>, terms: array<string, list<int>>}
      *     $snapshot Output of snapshot().
+     * @param list<string> $parts Subset of PARTS.
      * @throws RuntimeException Listing every part that could not be restored.
      */
-    public function restore(WP_Post $post, array $snapshot): void
+    public function restore(WP_Post $post, array $snapshot, array $parts = self::PARTS): void
     {
         $postId = (int) $post->ID;
         $steps = [
-            fn () => $this->updateRow($postId, $snapshot['post']),
-            fn () => $this->replaceMeta($postId, $snapshot['meta']),
-            fn () => $this->setTerms($postId, $snapshot['terms']),
+            'post' => fn () => $this->updateRow($postId, $snapshot['post']),
+            'meta' => fn () => $this->replaceMeta($postId, $snapshot['meta']),
+            'terms' => fn () => $this->setTerms($postId, $snapshot['terms']),
         ];
         $failures = [];
-        foreach ($steps as $step) {
+        foreach (array_intersect_key($steps, array_flip($parts)) as $step) {
             try {
                 $step();
             } catch (Throwable $e) {
@@ -158,6 +159,66 @@ class PostCloner
         return (string) preg_replace('/ \(Kopie\)$/u', '', $title);
     }
 
+    /** @throws WriteFailed */
+    private function cloneAsDraft(WP_Post $original, string $suffix, string $markerKey, string $label): int
+    {
+        $originalId = (int) $original->ID;
+        $cloneId = wp_insert_post(wp_slash([
+            'post_type' => (string) $original->post_type,
+            'post_status' => 'draft',
+            'post_title' => (string) $original->post_title . $suffix,
+            'post_content' => (string) $original->post_content,
+            'post_excerpt' => (string) $original->post_excerpt,
+            'post_parent' => (int) $original->post_parent,
+            'menu_order' => (int) $original->menu_order,
+            'comment_status' => (string) $original->comment_status,
+            'ping_status' => (string) $original->ping_status,
+            'post_password' => (string) $original->post_password,
+            'post_author' => get_current_user_id(),
+        ]), true);
+
+        if ($cloneId instanceof WP_Error || (int) $cloneId === 0) {
+            $reason = $cloneId instanceof WP_Error ? $cloneId->get_error_message() : 'unknown error';
+            throw new WriteFailed(
+                $label . ' konnte nicht angelegt werden.',
+                true,
+                null,
+                null,
+                null,
+                sprintf('Clone (%s) of post %d could not be created: %s', $markerKey, $originalId, $reason)
+            );
+        }
+
+        $cloneId = (int) $cloneId;
+        try {
+            $this->replaceMeta($cloneId, $this->ownMeta($originalId));
+            $this->setTerms($cloneId, $this->termIds($original));
+            if (update_post_meta($cloneId, $markerKey, $originalId) === false) {
+                throw new RuntimeException('Clone marker could not be written.');
+            }
+        } catch (Throwable $e) {
+            $this->discard($original, $cloneId, $e, $label . ' konnte nicht vollständig angelegt werden.');
+        }
+
+        return $cloneId;
+    }
+
+    /**
+     * Deletes a clone this class just created (never anything else) and reports the failure.
+     *
+     * @throws WriteFailed Always.
+     */
+    private function discard(WP_Post $original, int $cloneId, Throwable $cause, string $reason): never
+    {
+        $deleted = wp_delete_post($cloneId, true);
+        $detail = sprintf('Clone %d of post %d failed: %s', $cloneId, (int) $original->ID, $cause->getMessage());
+        if ($deleted) {
+            throw new WriteFailed($reason, true, null, null, $cause, $detail . '; clone deleted');
+        }
+
+        throw new WriteFailed($reason, false, $cloneId, null, $cause, $detail . '; clone could not be deleted');
+    }
+
     /**
      * @param array<string, string> $columns
      * @throws RuntimeException
@@ -172,16 +233,26 @@ class PostCloner
     }
 
     /**
-     * Raw meta of a post without SKIP_META (values as stored, serialized ones as strings).
+     * Stored meta of a post without SKIP_META: meta_value strings exactly as in the database.
      *
-     * @return array<string, list<mixed>>
+     * @return array<string, list<string|null>>
      */
     private function ownMeta(int $postId): array
     {
+        $db = $this->db();
+        $rows = $db->get_results(
+            $db->prepare(
+                "SELECT meta_key, meta_value FROM {$db->postmeta} WHERE post_id = %d ORDER BY meta_id",
+                $postId
+            ),
+            'ARRAY_A'
+        );
+
         $meta = [];
-        foreach ((array) get_post_meta($postId) as $key => $values) {
-            if (! in_array((string) $key, self::SKIP_META, true)) {
-                $meta[(string) $key] = array_values((array) $values);
+        foreach ((array) $rows as $row) {
+            $key = (string) $row['meta_key'];
+            if (! in_array($key, self::SKIP_META, true)) {
+                $meta[$key][] = $row['meta_value'] === null ? null : (string) $row['meta_value'];
             }
         }
 
@@ -189,25 +260,37 @@ class PostCloner
     }
 
     /**
-     * Makes the post's meta (except SKIP_META) exactly $meta.
+     * Makes the post's meta (except SKIP_META) exactly $meta; values are inserted as stored.
      *
-     * @param array<string, list<mixed>> $meta
+     * @param array<string, list<string|null>> $meta
      * @throws RuntimeException
      */
     private function replaceMeta(int $postId, array $meta): void
     {
-        foreach (array_keys($this->ownMeta($postId)) as $key) {
-            if (delete_post_meta($postId, $key) === false) {
-                throw new RuntimeException(sprintf('Meta "%s" of post %d could not be deleted.', $key, $postId));
-            }
-        }
-
-        foreach ($meta as $key => $values) {
-            foreach ($values as $value) {
-                if (add_post_meta($postId, $key, wp_slash(maybe_unserialize($value))) === false) {
-                    throw new RuntimeException(sprintf('Meta "%s" of post %d could not be written.', $key, $postId));
+        $db = $this->db();
+        try {
+            foreach (array_keys($this->ownMeta($postId)) as $key) {
+                if (delete_post_meta($postId, $key) === false) {
+                    throw new RuntimeException(sprintf('Meta "%s" of post %d could not be deleted.', $key, $postId));
                 }
             }
+
+            foreach ($meta as $key => $values) {
+                foreach ($values as $value) {
+                    $inserted = $db->insert(
+                        $db->postmeta,
+                        ['post_id' => $postId, 'meta_key' => $key, 'meta_value' => $value],
+                        ['%d', '%s', '%s']
+                    );
+                    if ($inserted === false) {
+                        throw new RuntimeException(
+                            sprintf('Meta "%s" of post %d could not be written.', $key, $postId)
+                        );
+                    }
+                }
+            }
+        } finally {
+            wp_cache_delete($postId, 'post_meta');
         }
     }
 
@@ -246,4 +329,14 @@ class PostCloner
             }
         }
     }
+
+    private function db(): \wpdb
+    {
+        if ($this->db === null) {
+            global $wpdb;
+            $this->db = $wpdb;
+        }
+
+        return $this->db;
+    }
 }
diff --git a/src/Integrations/WordPress/Status/PostDuplicateAbility.php b/src/Integrations/WordPress/Status/PostDuplicateAbility.php
index 704cadf..b0988b5 100644
--- a/src/Integrations/WordPress/Status/PostDuplicateAbility.php
+++ b/src/Integrations/WordPress/Status/PostDuplicateAbility.php
@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace LIT\MCP\Integrations\WordPress\Status;
 
 use LIT\MCP\Abilities\Ability;
+use LIT\MCP\Abilities\Errors;
 use LIT\MCP\Abilities\FollowUp;
 use LIT\MCP\Abilities\Rev;
 use LIT\MCP\Abilities\ToolResult;
@@ -125,6 +126,14 @@ final class PostDuplicateAbility implements Ability
             return $post;
         }
 
+        if ($post->post_status === 'trash') {
+            return Errors::invalidInput(
+                'Der Eintrag liegt im Papierkorb.',
+                ['post_id' => 'Eintrag liegt im Papierkorb'],
+                'Eintrag zuerst in WordPress wiederherstellen.'
+            );
+        }
+
         $type = PostGuard::postType((string) $post->post_type, $this->schema, 'create_posts');
 
         return $type instanceof WP_Error ? $type : $post;
diff --git a/src/Integrations/WordPress/Status/PostReplaceWithCopyAbility.php b/src/Integrations/WordPress/Status/PostReplaceWithCopyAbility.php
index 99bd823..7f2c403 100644
--- a/src/Integrations/WordPress/Status/PostReplaceWithCopyAbility.php
+++ b/src/Integrations/WordPress/Status/PostReplaceWithCopyAbility.php
@@ -23,10 +23,12 @@ use WP_Post;
  * (spec §6.2). ID, URL, status and menu items of the original stay. rev of the original
  * (from lit/content-get) is required so parallel edits are never overwritten. All or
  * nothing (spec §8.2): the original's title/content/excerpt, meta and terms are
- * snapshotted and restored if the swap fails (WriteFailed → lit_write_failed, or
- * lit_partial_write when the restore was incomplete). A revision is taken first. The
- * copy then goes to the trash – refused up front when the trash is disabled, because
- * wp_trash_post() would delete permanently then.
+ * snapshotted and the parts reached are restored if the swap fails (WriteFailed →
+ * lit_write_failed, or lit_partial_write when the restore was incomplete). Before the
+ * swap, a full clone of the original is put into the trash as backup (ruling P12; meta
+ * and terms are not revisioned) and a revision is taken. The copy then goes to the
+ * trash as well – refused up front when the trash is disabled, because wp_trash_post()
+ * would delete permanently then.
  */
 final class PostReplaceWithCopyAbility implements Ability
 {
@@ -59,8 +61,11 @@ final class PostReplaceWithCopyAbility implements Ability
     {
         return 'Übernimmt Titel, Inhalt, Felder/Meta und Begriffe einer mit lit-post-duplicate erstellten Kopie '
             . 'ins Original. ID, URL, Status und Menüeinträge des Originals bleiben; vorher entsteht eine '
-            . 'Revision des Originals, die Kopie kommt danach in den Papierkorb. rev des Originals aus '
-            . 'lit-content-get ist Pflicht. Erst nach Rückfrage mit confirm: true aufrufen.';
+            . 'Revision und eine vollständige Sicherung des Originals (im Papierkorb, backup_id), die Kopie kommt '
+            . 'danach in den Papierkorb. Die Kopie muss Entwurf oder ausstehend sein. rev des Originals aus '
+            . 'lit-content-get ist Pflicht; sie deckt nur Titel, Inhalt, Auszug und Status ab – Felder/Meta, die '
+            . 'nach dem Duplizieren direkt am Original geändert wurden, werden überschrieben (stehen aber in der '
+            . 'Sicherung). Erst nach Rückfrage mit confirm: true aufrufen.';
     }
 
     public function inputSchema(): array
@@ -83,7 +88,7 @@ final class PostReplaceWithCopyAbility implements Ability
 
     public function outputSchema(): ?array
     {
-        return ToolResult::schema();
+        return ToolResult::schema(['backup_id' => ['type' => 'integer']], ['backup_id']);
     }
 
     public function annotations(): array
@@ -123,14 +128,18 @@ final class PostReplaceWithCopyAbility implements Ability
             throw new WriteFailed(self::REASON, true, $originalId, null, $e);
         }
 
+        // Throws WriteFailed (backup deleted again) before anything touches the original.
+        $backupId = $this->cloner->backup($original);
         $revisionId = RevisionPoint::capture($originalId);
         try {
             $this->cloner->replace($original, $copy);
+        } catch (ReplaceFailed $e) {
+            $this->rollBack($original, $snapshot, $e->parts, $revisionId, $e->getPrevious() ?? $e);
         } catch (Throwable $e) {
-            $this->rollBack($original, $snapshot, $revisionId, $e);
+            $this->rollBack($original, $snapshot, PostCloner::PARTS, $revisionId, $e);
         }
 
-        return $this->result($original, $copy, $input, $revisionId);
+        return $this->result($original, $copy, $input, $revisionId, $backupId);
     }
 
     /**
@@ -160,11 +169,19 @@ final class PostReplaceWithCopyAbility implements Ability
             );
         }
 
-        if ($copy->post_status === 'trash') {
+        if ($original->post_status === 'trash') {
             return Errors::invalidInput(
-                'Die Kopie liegt im Papierkorb.',
-                ['copy_id' => 'Kopie liegt im Papierkorb'],
-                'Kopie in WordPress wiederherstellen oder mit lit-post-duplicate eine neue Kopie erstellen.'
+                'Das Original liegt im Papierkorb.',
+                ['original_id' => 'Original liegt im Papierkorb'],
+                'Original zuerst in WordPress wiederherstellen.'
+            );
+        }
+
+        if (! in_array($copy->post_status, ['draft', 'pending'], true)) {
+            return Errors::invalidInput(
+                sprintf('Die Kopie hat den Status "%s"; übernommen wird nur ein Entwurf.', $copy->post_status),
+                ['copy_id' => 'Kopie muss Entwurf oder ausstehend sein'],
+                'Mit lit-post-duplicate eine neue Kopie erstellen (bzw. die Kopie in WordPress wiederherstellen).'
             );
         }
 
@@ -187,7 +204,7 @@ final class PostReplaceWithCopyAbility implements Ability
      * @param array<string, mixed> $input
      * @return array<string, mixed>
      */
-    private function result(WP_Post $original, WP_Post $copy, array $input, ?int $revisionId): array
+    private function result(WP_Post $original, WP_Post $copy, array $input, ?int $revisionId, int $backupId): array
     {
         $originalId = (int) $original->ID;
         $copyId = (int) $copy->ID;
@@ -226,9 +243,10 @@ final class PostReplaceWithCopyAbility implements Ability
         $updated = get_post($originalId);
         $updated = $updated instanceof WP_Post ? $updated : $original;
         $statusNote = sprintf(
-            '; Status bleibt %s, %s.',
+            '; Status bleibt %s, %s, der vorherige Stand liegt als Sicherung ID %d im Papierkorb.',
             $original->post_status,
-            $trashed ? 'Kopie liegt im Papierkorb' : 'Kopie besteht weiter'
+            $trashed ? 'Kopie liegt im Papierkorb' : 'Kopie besteht weiter',
+            $backupId
         );
 
         $result = ToolResult::ok($summary . $statusNote)
@@ -243,20 +261,27 @@ final class PostReplaceWithCopyAbility implements Ability
             ->logId(is_int($logId) ? $logId : null)
             ->urls((string) get_permalink($originalId), (string) get_edit_post_link($originalId, 'raw'))
             ->warnings($warnings)
+            ->with('backup_id', $backupId)
             ->toArray();
     }
 
     /**
      * @param array{post: array<string, string>, meta: array<string, list<mixed>>, terms: array<string, list<int>>}
      *     $snapshot Output of PostCloner::snapshot().
+     * @param list<string> $parts Parts replace() had (possibly) written.
      * @throws WriteFailed Always – rolledBack tells whether the original was restored completely.
      */
-    private function rollBack(WP_Post $original, array $snapshot, ?int $revisionId, Throwable $cause): never
-    {
+    private function rollBack(
+        WP_Post $original,
+        array $snapshot,
+        array $parts,
+        ?int $revisionId,
+        Throwable $cause
+    ): never {
         $originalId = (int) $original->ID;
         $detail = sprintf('Replace of post %d failed: %s', $originalId, $cause->getMessage());
         try {
-            $this->cloner->restore($original, $snapshot);
+            $this->cloner->restore($original, $snapshot, $parts);
         } catch (Throwable $e) {
             $ignored = [];
             FollowUp::run(
diff --git a/src/Integrations/WordPress/Status/ReplaceFailed.php b/src/Integrations/WordPress/Status/ReplaceFailed.php
new file mode 100644
index 0000000..0a3a056
--- /dev/null
+++ b/src/Integrations/WordPress/Status/ReplaceFailed.php
@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Integrations\WordPress\Status;
+
+use RuntimeException;
+use Throwable;
+
+/**
+ * Thrown by PostCloner::replace(). $parts lists the parts of the original replace()
+ * had started to write (post, meta, terms) – only those need to be restored.
+ */
+final class ReplaceFailed extends RuntimeException
+{
+    /** @param list<string> $parts */
+    public function __construct(public readonly array $parts, Throwable $previous)
+    {
+        parent::__construct($previous->getMessage(), 0, $previous);
+    }
+}
diff --git a/tests/Unit/Integrations/WordPress/Status/PostClonerTest.php b/tests/Unit/Integrations/WordPress/Status/PostClonerTest.php
index 1899100..491ce4a 100644
--- a/tests/Unit/Integrations/WordPress/Status/PostClonerTest.php
+++ b/tests/Unit/Integrations/WordPress/Status/PostClonerTest.php
@@ -7,13 +7,54 @@ namespace LIT\MCP\Tests\Unit\Integrations\WordPress\Status;
 use Brain\Monkey\Functions;
 use LIT\MCP\Abilities\WriteFailed;
 use LIT\MCP\Integrations\WordPress\Status\PostCloner;
+use LIT\MCP\Integrations\WordPress\Status\ReplaceFailed;
 use LIT\MCP\Tests\Unit\TestCase;
+use Mockery;
 use RuntimeException;
 use WP_Error;
 use WP_Post;
 
 final class PostClonerTest extends TestCase
 {
+    /** @var array<int, array<string, list<string|null>>> Stored meta by post ID, as meta_value strings. */
+    private array $meta = [];
+
+    /** @var list<array{0: int, 1: string, 2: string|null}> Raw postmeta inserts. */
+    private array $inserts = [];
+
+    private bool $insertFails = false;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+        Functions\when('wp_cache_delete')->justReturn(true);
+    }
+
+    private function cloner(): PostCloner
+    {
+        $db = Mockery::mock(\wpdb::class)->makePartial();
+        $db->allows('get_results')->andReturnUsing(function (string $sql): array {
+            preg_match('/post_id = (\d+)/', $sql, $match);
+            $rows = [];
+            foreach ($this->meta[(int) $match[1]] ?? [] as $key => $values) {
+                foreach ($values as $value) {
+                    $rows[] = ['meta_key' => $key, 'meta_value' => $value];
+                }
+            }
+
+            return $rows;
+        });
+        $db->allows('insert')->andReturnUsing(function (string $table, array $data, array $format) {
+            self::assertSame('wp_postmeta', $table);
+            self::assertSame(['%d', '%s', '%s'], $format);
+            $this->inserts[] = [$data['post_id'], $data['meta_key'], $data['meta_value']];
+
+            return $this->insertFails ? false : 1;
+        });
+
+        return new PostCloner($db);
+    }
+
     private function original(): WP_Post
     {
         return new WP_Post([
@@ -41,33 +82,64 @@ final class PostClonerTest extends TestCase
     public function testDuplicateCopiesContentMetaAndTermsAsDraft(): void
     {
         Functions\when('get_current_user_id')->justReturn(4);
-        Functions\when('maybe_unserialize')->returnArg();
-        Functions\expect('wp_insert_post')->once()->with($this->draftMatcher(), true)->andReturn(77);
-        Functions\when('get_post_meta')->alias(static fn (int $id) => $id === 5
-            ? [
+        Functions\expect('wp_insert_post')->once()->with($this->draftMatcher('Team (Kopie)'), true)->andReturn(77);
+        $this->meta = [
+            5 => [
                 '_edit_lock' => ['123:1'],
                 '_edit_last' => ['1'],
                 '_wp_old_slug' => ['team-alt'],
+                '_lit_mcp_backup_of' => ['3'],
                 '_et_pb_use_builder' => ['on'],
                 '_et_pb_use_divi_5' => ['on'],
                 '_wp_page_template' => ['page-template-blank.php'],
                 '_thumbnail_id' => ['31'],
                 'role' => ['Leitung'],
-            ]
-            : ['_edit_lock' => ['999:4'], '_et_pb_use_builder' => ['off']]);
-        // Meta a save hook put on the fresh copy is replaced by the original's.
+            ],
+            // Meta a save hook put on the fresh copy is replaced by the original's.
+            77 => ['_edit_lock' => ['999:4'], '_et_pb_use_builder' => ['off']],
+        ];
         Functions\expect('delete_post_meta')->once()->with(77, '_et_pb_use_builder');
-        Functions\expect('add_post_meta')->once()->with(77, '_et_pb_use_builder', 'on');
-        Functions\expect('add_post_meta')->once()->with(77, '_et_pb_use_divi_5', 'on');
-        Functions\expect('add_post_meta')->once()->with(77, '_wp_page_template', 'page-template-blank.php');
-        Functions\expect('add_post_meta')->once()->with(77, '_thumbnail_id', '31');
-        Functions\expect('add_post_meta')->once()->with(77, 'role', 'Leitung');
         Functions\when('get_object_taxonomies')->justReturn(['category']);
         Functions\when('wp_get_object_terms')->justReturn([4, 9]);
         Functions\expect('wp_set_object_terms')->once()->with(77, [4, 9], 'category', false);
         Functions\expect('update_post_meta')->once()->with(77, '_lit_mcp_copy_of', 5);
 
-        self::assertSame(77, (new PostCloner())->duplicate($this->original()));
+        self::assertSame(77, $this->cloner()->duplicate($this->original()));
+        self::assertSame([
+            [77, '_et_pb_use_builder', 'on'],
+            [77, '_et_pb_use_divi_5', 'on'],
+            [77, '_wp_page_template', 'page-template-blank.php'],
+            [77, '_thumbnail_id', '31'],
+            [77, 'role', 'Leitung'],
+        ], $this->inserts);
+    }
+
+    public function testMetaIsCopiedByteExact(): void
+    {
+        Functions\when('get_current_user_id')->justReturn(4);
+        Functions\when('wp_insert_post')->justReturn(77);
+        Functions\when('get_object_taxonomies')->justReturn([]);
+        Functions\when('update_post_meta')->justReturn(true);
+        $raw = [
+            'path' => ['a:1:{s:1:"p";s:9:"C:\\new\\x\\";}'],
+            'quoted' => ['Er sagte \\"hallo\\"'],
+            'flag' => ['b:0;'],
+            'object' => ['O:8:"stdClass":1:{s:1:"a";i:1;}'],
+            'empty' => [''],
+            'null' => [null],
+        ];
+        $this->meta = [5 => $raw];
+
+        $this->cloner()->duplicate($this->original());
+
+        self::assertSame([
+            [77, 'path', 'a:1:{s:1:"p";s:9:"C:\\new\\x\\";}'],
+            [77, 'quoted', 'Er sagte \\"hallo\\"'],
+            [77, 'flag', 'b:0;'],
+            [77, 'object', 'O:8:"stdClass":1:{s:1:"a";i:1;}'],
+            [77, 'empty', ''],
+            [77, 'null', null],
+        ], $this->inserts);
     }
 
     public function testDuplicateFailureThrows(): void
@@ -77,20 +149,19 @@ final class PostClonerTest extends TestCase
 
         $this->expectException(RuntimeException::class);
 
-        (new PostCloner())->duplicate($this->original());
+        $this->cloner()->duplicate($this->original());
     }
 
     public function testDuplicateFailingAfterInsertDeletesTheNewDraft(): void
     {
         Functions\when('get_current_user_id')->justReturn(4);
-        Functions\when('maybe_unserialize')->returnArg();
         Functions\when('wp_insert_post')->justReturn(77);
-        Functions\when('get_post_meta')->alias(static fn (int $id) => $id === 5 ? ['role' => ['Leitung']] : []);
-        Functions\when('add_post_meta')->justReturn(false);
+        $this->meta = [5 => ['role' => ['Leitung']]];
+        $this->insertFails = true;
         Functions\expect('wp_delete_post')->once()->with(77, true)->andReturn(new WP_Post(['ID' => 77]));
 
         try {
-            (new PostCloner())->duplicate($this->original());
+            $this->cloner()->duplicate($this->original());
             self::fail('WriteFailed expected');
         } catch (WriteFailed $e) {
             self::assertTrue($e->rolledBack);
@@ -100,15 +171,13 @@ final class PostClonerTest extends TestCase
     public function testDuplicateReportsALeftoverDraftWhenItCannotBeDeleted(): void
     {
         Functions\when('get_current_user_id')->justReturn(4);
-        Functions\when('maybe_unserialize')->returnArg();
         Functions\when('wp_insert_post')->justReturn(77);
-        Functions\when('get_post_meta')->justReturn([]);
         Functions\when('get_object_taxonomies')->justReturn(['category']);
         Functions\when('wp_get_object_terms')->justReturn(new WP_Error('x', 'kaputt'));
         Functions\when('wp_delete_post')->justReturn(false);
 
         try {
-            (new PostCloner())->duplicate($this->original());
+            $this->cloner()->duplicate($this->original());
             self::fail('WriteFailed expected');
         } catch (WriteFailed $e) {
             self::assertFalse($e->rolledBack);
@@ -116,100 +185,153 @@ final class PostClonerTest extends TestCase
         }
     }
 
+    public function testBackupIsAFullCloneInTheTrash(): void
+    {
+        Functions\when('get_current_user_id')->justReturn(4);
+        Functions\expect('wp_insert_post')->once()->with($this->draftMatcher('Team (Sicherung)'), true)->andReturn(88);
+        $this->meta = [5 => ['_et_pb_use_builder' => ['on'], '_lit_mcp_copy_of' => ['1']]];
+        Functions\when('get_object_taxonomies')->justReturn(['category']);
+        Functions\when('wp_get_object_terms')->justReturn([4]);
+        Functions\expect('wp_set_object_terms')->once()->with(88, [4], 'category', false);
+        Functions\expect('update_post_meta')->once()->with(88, '_lit_mcp_backup_of', 5)->andReturn(12);
+        Functions\expect('wp_trash_post')->once()->with(88)->andReturn(new WP_Post(['ID' => 88]));
+        Functions\when('get_post_status')->justReturn('trash');
+        Functions\expect('wp_delete_post')->never();
+
+        self::assertSame(88, $this->cloner()->backup($this->original()));
+        self::assertSame([[88, '_et_pb_use_builder', 'on']], $this->inserts);
+    }
+
+    public function testABackupThatCannotBeTrashedIsDeletedAgain(): void
+    {
+        Functions\when('get_current_user_id')->justReturn(4);
+        Functions\when('wp_insert_post')->justReturn(88);
+        Functions\when('get_object_taxonomies')->justReturn([]);
+        Functions\when('update_post_meta')->justReturn(12);
+        Functions\when('wp_trash_post')->justReturn(new WP_Post(['ID' => 88]));
+        Functions\when('get_post_status')->justReturn('draft');
+        Functions\expect('wp_delete_post')->once()->with(88, true)->andReturn(new WP_Post(['ID' => 88]));
+
+        try {
+            $this->cloner()->backup($this->original());
+            self::fail('WriteFailed expected');
+        } catch (WriteFailed $e) {
+            self::assertTrue($e->rolledBack);
+            self::assertSame('lit_write_failed', $e->toError()->get_error_code());
+        }
+    }
+
     public function testReplaceOverwritesContentMetaAndTermsButKeepsTheOriginalsIdentity(): void
     {
-        Functions\when('maybe_unserialize')->returnArg();
         Functions\expect('wp_update_post')->once()->with([
             'ID' => 5,
             'post_title' => 'Team',
             'post_content' => 'neu',
             'post_excerpt' => 'Neu kurz',
         ], true)->andReturn(5);
-        Functions\when('get_post_meta')->alias(static fn (int $id) => $id === 5
-            ? ['_edit_lock' => ['1'], '_wp_old_slug' => ['alt'], 'role' => ['Alt'], 'city' => ['Trier']]
-            : ['_lit_mcp_copy_of' => ['5'], '_edit_last' => ['4'], 'role' => ['Neu']]);
+        $this->meta = [
+            5 => ['_edit_lock' => ['1'], '_wp_old_slug' => ['alt'], 'role' => ['Alt'], 'city' => ['Trier']],
+            77 => ['_lit_mcp_copy_of' => ['5'], '_edit_last' => ['4'], 'role' => ['Neu']],
+        ];
         Functions\expect('delete_post_meta')->once()->with(5, 'role');
         Functions\expect('delete_post_meta')->once()->with(5, 'city');
-        Functions\expect('add_post_meta')->once()->with(5, 'role', 'Neu');
         Functions\when('get_object_taxonomies')->justReturn(['category']);
         Functions\when('wp_get_object_terms')->justReturn([12]);
         Functions\expect('wp_set_object_terms')->once()->with(5, [12], 'category', false);
 
-        (new PostCloner())->replace($this->original(), $this->copy());
+        $this->cloner()->replace($this->original(), $this->copy());
+
+        self::assertSame([[5, 'role', 'Neu']], $this->inserts);
     }
 
-    public function testReplaceThrowsWhenWordPressRejectsTheUpdate(): void
+    public function testAReplaceRejectedByWordPressNamesOnlyThePostRow(): void
     {
         Functions\when('wp_update_post')->justReturn(new WP_Error('x', 'kaputt'));
         Functions\expect('delete_post_meta')->never();
 
-        $this->expectException(RuntimeException::class);
-
-        (new PostCloner())->replace($this->original(), $this->copy());
+        try {
+            $this->cloner()->replace($this->original(), $this->copy());
+            self::fail('ReplaceFailed expected');
+        } catch (ReplaceFailed $e) {
+            self::assertSame(['post'], $e->parts);
+        }
     }
 
-    public function testReplaceThrowsWhenTermsCannotBeSet(): void
+    public function testAFailingTermStepNamesAllParts(): void
     {
         Functions\when('wp_update_post')->justReturn(5);
-        Functions\when('get_post_meta')->justReturn([]);
         Functions\when('get_object_taxonomies')->justReturn(['category']);
         Functions\when('wp_get_object_terms')->justReturn([12]);
         Functions\when('wp_set_object_terms')->justReturn(new WP_Error('x', 'kaputt'));
 
-        $this->expectException(RuntimeException::class);
-
-        (new PostCloner())->replace($this->original(), $this->copy());
+        try {
+            $this->cloner()->replace($this->original(), $this->copy());
+            self::fail('ReplaceFailed expected');
+        } catch (ReplaceFailed $e) {
+            self::assertSame(['post', 'meta', 'terms'], $e->parts);
+        }
     }
 
     public function testSnapshotAndRestoreBringBackRowMetaAndTerms(): void
     {
-        $meta = ['_edit_lock' => ['1'], 'role' => ['Alt']];
-        Functions\when('get_post_meta')->alias(static function () use (&$meta): array {
-            return $meta;
-        });
+        $this->meta = [5 => ['_edit_lock' => ['1'], 'role' => ['b:0;']]];
         Functions\when('get_object_taxonomies')->justReturn(['category']);
         Functions\when('wp_get_object_terms')->justReturn([4]);
 
-        $cloner = new PostCloner();
+        $cloner = $this->cloner();
         $snapshot = $cloner->snapshot($this->original());
 
         self::assertSame(['post_title' => 'Team', 'post_content' => '<!-- wp:divi/section /-->', 'post_excerpt' => 'Kurz'], $snapshot['post']);
-        self::assertSame(['role' => ['Alt']], $snapshot['meta']);
+        self::assertSame(['role' => ['b:0;']], $snapshot['meta']);
         self::assertSame(['category' => [4]], $snapshot['terms']);
 
-        $meta = ['_edit_lock' => ['1'], 'role' => ['Neu'], 'city' => ['Trier']];
-        Functions\when('maybe_unserialize')->returnArg();
+        $this->meta = [5 => ['_edit_lock' => ['1'], 'role' => ['Neu'], 'city' => ['Trier']]];
         Functions\expect('wp_update_post')->once()
             ->with(array_merge(['ID' => 5], $snapshot['post']), true)->andReturn(5);
         Functions\expect('delete_post_meta')->once()->with(5, 'role');
         Functions\expect('delete_post_meta')->once()->with(5, 'city');
-        Functions\expect('add_post_meta')->once()->with(5, 'role', 'Alt');
         Functions\expect('wp_set_object_terms')->once()->with(5, [4], 'category', false);
 
         $cloner->restore($this->original(), $snapshot);
+
+        self::assertSame([[5, 'role', 'b:0;']], $this->inserts);
+    }
+
+    public function testRestoreWritesOnlyThePartsReached(): void
+    {
+        Functions\expect('wp_update_post')->once()->andReturn(5);
+        Functions\expect('delete_post_meta')->never();
+        Functions\expect('wp_set_object_terms')->never();
+
+        $this->cloner()->restore($this->original(), [
+            'post' => ['post_title' => 'Team', 'post_content' => '', 'post_excerpt' => ''],
+            'meta' => ['role' => ['Alt']],
+            'terms' => ['category' => [4]],
+        ], ['post']);
+
+        self::assertSame([], $this->inserts);
     }
 
     public function testRestoreTriesEveryPartAndReportsFailures(): void
     {
         Functions\when('wp_update_post')->justReturn(new WP_Error('x', 'kaputt'));
-        Functions\when('get_post_meta')->justReturn([]);
         Functions\expect('wp_set_object_terms')->once()->with(5, [4], 'category', false);
 
         $this->expectException(RuntimeException::class);
         $this->expectExceptionMessage('Restore incomplete');
 
-        (new PostCloner())->restore($this->original(), [
+        $this->cloner()->restore($this->original(), [
             'post' => ['post_title' => 'Team', 'post_content' => '', 'post_excerpt' => ''],
             'meta' => [],
             'terms' => ['category' => [4]],
         ]);
     }
 
-    private function draftMatcher(): \Mockery\Matcher\Closure
+    private function draftMatcher(string $title): \Mockery\Matcher\Closure
     {
-        return \Mockery::on(static fn (array $data): bool => $data['post_status'] === 'draft'
+        return Mockery::on(static fn (array $data): bool => $data['post_status'] === 'draft'
             && $data['post_type'] === 'page'
-            && $data['post_title'] === 'Team (Kopie)'
+            && $data['post_title'] === $title
             && $data['post_content'] === '<!-- wp:divi/section /-->'
             && $data['post_excerpt'] === 'Kurz'
             && $data['post_parent'] === 2
diff --git a/tests/Unit/Integrations/WordPress/Status/PostDuplicateAbilityTest.php b/tests/Unit/Integrations/WordPress/Status/PostDuplicateAbilityTest.php
index 4abe60c..1f1542e 100644
--- a/tests/Unit/Integrations/WordPress/Status/PostDuplicateAbilityTest.php
+++ b/tests/Unit/Integrations/WordPress/Status/PostDuplicateAbilityTest.php
@@ -68,6 +68,17 @@ final class PostDuplicateAbilityTest extends TestCase
         self::assertSame('lit_forbidden', $result->get_error_code());
     }
 
+    public function testATrashedOriginalIsRefused(): void
+    {
+        $this->original->post_status = 'trash';
+        $cloner = Mockery::mock(PostCloner::class);
+        $cloner->expects('duplicate')->never();
+
+        $result = $this->ability($cloner, Mockery::mock(ChangeLog::class))->execute(['post_id' => 5]);
+
+        self::assertSame('lit_validation_failed', $result->get_error_code());
+    }
+
     public function testIsIndirectAndNotIdempotent(): void
     {
         $ability = $this->ability(Mockery::mock(PostCloner::class), Mockery::mock(ChangeLog::class));
diff --git a/tests/Unit/Integrations/WordPress/Status/PostReplaceWithCopyAbilityTest.php b/tests/Unit/Integrations/WordPress/Status/PostReplaceWithCopyAbilityTest.php
index 6b8711e..044a969 100644
--- a/tests/Unit/Integrations/WordPress/Status/PostReplaceWithCopyAbilityTest.php
+++ b/tests/Unit/Integrations/WordPress/Status/PostReplaceWithCopyAbilityTest.php
@@ -11,6 +11,7 @@ use LIT\MCP\ChangeLog\ChangeLog;
 use LIT\MCP\Integrations\WordPress\Schema\ContentSchema;
 use LIT\MCP\Integrations\WordPress\Status\PostCloner;
 use LIT\MCP\Integrations\WordPress\Status\PostReplaceWithCopyAbility;
+use LIT\MCP\Integrations\WordPress\Status\ReplaceFailed;
 use LIT\MCP\Tests\Unit\TestCase;
 use Mockery;
 use RuntimeException;
@@ -80,10 +81,23 @@ final class PostReplaceWithCopyAbilityTest extends TestCase
         self::assertSame('lit_validation_failed', $result->get_error_code());
     }
 
-    public function testATrashedCopyIsRefused(): void
+    /** @return list<array{0: string, 1: string}> */
+    public function refusedStatuses(): array
     {
-        $this->copy->post_status = 'trash';
+        return [
+            'trashed copy' => ['copy', 'trash'],
+            'published copy' => ['copy', 'publish'],
+            'scheduled copy' => ['copy', 'future'],
+            'trashed original' => ['original', 'trash'],
+        ];
+    }
+
+    /** @dataProvider refusedStatuses */
+    public function testRefusesCopiesThatAreNoDraftAndTrashedOriginals(string $which, string $status): void
+    {
+        $this->{$which}->post_status = $status;
         $cloner = Mockery::mock(PostCloner::class);
+        $cloner->expects('backup')->never();
         $cloner->expects('replace')->never();
 
         $result = $this->ability($cloner, Mockery::mock(ChangeLog::class))->execute($this->input());
@@ -91,6 +105,21 @@ final class PostReplaceWithCopyAbilityTest extends TestCase
         self::assertSame('lit_validation_failed', $result->get_error_code());
     }
 
+    public function testAPendingCopyIsAccepted(): void
+    {
+        $this->copy->post_status = 'pending';
+        $this->revisionAt900();
+        $cloner = Mockery::mock(PostCloner::class);
+        $cloner->allows('snapshot')->andReturn(self::SNAPSHOT);
+        $cloner->allows('backup')->andReturn(88);
+        $cloner->expects('replace');
+        Functions\when('wp_trash_post')->justReturn(new WP_Post(['ID' => 77]));
+        $log = Mockery::mock(ChangeLog::class);
+        $log->allows('record')->andReturn(11);
+
+        self::assertTrue($this->ability($cloner, $log)->execute($this->input())['ok']);
+    }
+
     public function testAStaleRevOfTheOriginalIsRefused(): void
     {
         $cloner = Mockery::mock(PostCloner::class);
@@ -125,6 +154,10 @@ final class PostReplaceWithCopyAbilityTest extends TestCase
             $order[] = 'snapshot';
             return self::SNAPSHOT;
         });
+        $cloner->expects('backup')->with($this->original)->andReturnUsing(static function () use (&$order): int {
+            $order[] = 'backup';
+            return 88;
+        });
         $cloner->expects('replace')->with($this->original, $this->copy)->andReturnUsing(static function () use (&$order): void {
             $order[] = 'replace';
         });
@@ -138,7 +171,9 @@ final class PostReplaceWithCopyAbilityTest extends TestCase
 
         $result = $this->ability($cloner, $log)->execute($this->input());
 
-        self::assertSame(['snapshot', 'revision', 'replace', 'trash'], $order);
+        self::assertSame(['snapshot', 'backup', 'revision', 'replace', 'trash'], $order);
+        self::assertSame(88, $result['backup_id']);
+        self::assertStringContainsString('Sicherung ID 88 im Papierkorb', $result['summary']);
         self::assertSame(900, $result['revision_id']);
         self::assertSame(11, $result['log_id']);
         self::assertSame(Rev::ofPost($this->original), $result['rev']);
@@ -151,6 +186,7 @@ final class PostReplaceWithCopyAbilityTest extends TestCase
         $this->revisionAt900();
         $cloner = Mockery::mock(PostCloner::class);
         $cloner->allows('snapshot')->andReturn(self::SNAPSHOT);
+        $cloner->allows('backup')->andReturn(88);
         $cloner->expects('replace');
         Functions\when('wp_trash_post')->justReturn(false);
         $log = Mockery::mock(ChangeLog::class);
@@ -168,8 +204,9 @@ final class PostReplaceWithCopyAbilityTest extends TestCase
         $this->revisionAt900();
         $cloner = Mockery::mock(PostCloner::class);
         $cloner->allows('snapshot')->andReturn(self::SNAPSHOT);
-        $cloner->expects('replace')->andThrow(new RuntimeException('meta kaputt'));
-        $cloner->expects('restore')->with($this->original, self::SNAPSHOT);
+        $cloner->allows('backup')->andReturn(88);
+        $cloner->expects('replace')->andThrow(new ReplaceFailed(['post'], new RuntimeException('row kaputt')));
+        $cloner->expects('restore')->with($this->original, self::SNAPSHOT, ['post']);
         Functions\expect('wp_trash_post')->never();
 
         try {
@@ -186,8 +223,9 @@ final class PostReplaceWithCopyAbilityTest extends TestCase
         $this->revisionAt900();
         $cloner = Mockery::mock(PostCloner::class);
         $cloner->allows('snapshot')->andReturn(self::SNAPSHOT);
-        $cloner->expects('replace')->andThrow(new RuntimeException('meta kaputt'));
-        $cloner->expects('restore')->andThrow(new RuntimeException('Restore incomplete: terms'));
+        $cloner->allows('backup')->andReturn(88);
+        $cloner->expects('replace')->andThrow(new RuntimeException('hook kaputt'));
+        $cloner->expects('restore')->with($this->original, self::SNAPSHOT, PostCloner::PARTS)->andThrow(new RuntimeException('Restore incomplete: terms'));
         Functions\expect('wp_trash_post')->never();
         $log = Mockery::mock(ChangeLog::class);
         $log->expects('record')
@@ -205,11 +243,30 @@ final class PostReplaceWithCopyAbilityTest extends TestCase
         }
     }
 
+    public function testAFailedBackupAbortsBeforeTheOriginalIsTouched(): void
+    {
+        $cloner = Mockery::mock(PostCloner::class);
+        $cloner->allows('snapshot')->andReturn(self::SNAPSHOT);
+        $cloner->expects('backup')->andThrow(new WriteFailed('Die Sicherung konnte nicht angelegt werden.', true));
+        $cloner->expects('replace')->never();
+        $cloner->expects('restore')->never();
+        Functions\expect('wp_save_post_revision')->never();
+        Functions\expect('wp_trash_post')->never();
+
+        try {
+            $this->ability($cloner, Mockery::mock(ChangeLog::class))->execute($this->input());
+            self::fail('WriteFailed expected');
+        } catch (WriteFailed $e) {
+            self::assertSame('lit_write_failed', $e->toError()->get_error_code());
+        }
+    }
+
     public function testRequiresRevAndIsDestructive(): void
     {
         $ability = $this->ability(Mockery::mock(PostCloner::class), Mockery::mock(ChangeLog::class));
 
         self::assertContains('rev', $ability->inputSchema()['required']);
+        self::assertContains('backup_id', $ability->outputSchema()['required']);
         self::assertTrue($ability->annotations()['destructive']);
         self::assertFalse($ability->annotations()['idempotent']);
         self::assertFalse($ability->isDirect());