diff --git a/src/Integrations/Divi/Pages/DiviInsertAbility.php b/src/Integrations/Divi/Pages/DiviInsertAbility.php
index 8a284dc..addfa9e 100644
--- a/src/Integrations/Divi/Pages/DiviInsertAbility.php
+++ b/src/Integrations/Divi/Pages/DiviInsertAbility.php
@@ -6,6 +6,9 @@ namespace LIT\MCP\Integrations\Divi\Pages;
 
 use LIT\MCP\Abilities\Annotations;
 use LIT\MCP\Abilities\Errors;
+use LIT\MCP\Integrations\Divi\BlockTree\Block;
+use LIT\MCP\Integrations\Divi\Compose\LoopContext;
+use LIT\MCP\Integrations\Divi\Compose\VariableRef;
 use LIT\MCP\Integrations\Divi\Release\DiviFeature;
 use WP_Error;
 
@@ -17,6 +20,9 @@ defined('ABSPATH') || exit;
  * validated first and every error is returned together; the blocks come only from Composer
  * (client values pass its choke point) and enter the tree only through TreeEditor::insert(),
  * which also wraps the first section of an empty page in divi/placeholder (ruling S9).
+ *
+ * Loop content (ruling X3): all new nodes share the loop scope of the target parent. A loop a new node of this
+ * call switches on counts only once it is saved – with loop content in the same call the insert fails closed.
  */
 final class DiviInsertAbility extends DiviWriteAbility
 {
@@ -97,7 +103,18 @@ final class DiviInsertAbility extends DiviWriteAbility
             ]);
         }
 
-        $composed = $composition->composer()->compose($nodes, $position['parent'], 'nodes', $context);
+        $scope = self::loopAt($page->index, $position['parent']);
+        $composed = $composition->inLoop($scope)->composer()->compose($nodes, $position['parent'], 'nodes', $context);
+        if (self::startsLoop($composed['blocks']) && self::hasLoopContent($nodes)) {
+            return Errors::invalidInput(
+                'Schleifen-Inhalte unter einer neuen Divi-Schleife gehen nicht in einem Aufruf; nichts wurde '
+                    . 'gespeichert.',
+                ['nodes' => 'Die Schleife eines neuen Elements gilt erst nach dem Speichern: zuerst das Element mit '
+                    . 'Schleife einfügen, dann die Schleifen-Inhalte mit lit-divi-insert (parent = Pfad-ID des '
+                    . 'Elements) ergänzen']
+            );
+        }
+
         if ($composed['errors'] !== []) {
             return DiviErrors::composed($composed, 'Knoten sind ungültig; nichts wurde gespeichert.');
         }
@@ -117,4 +134,38 @@ final class DiviInsertAbility extends DiviWriteAbility
 
         return $change;
     }
+
+    /**
+     * Whether one of $blocks or a descendant switches a loop on.
+     *
+     * @param list<Block> $blocks
+     */
+    private static function startsLoop(array $blocks): bool
+    {
+        foreach ($blocks as $block) {
+            if (LoopContext::enabled($block->attrs()) || self::startsLoop($block->children())) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Whether the input names loop content: a {{loop:…}} placeholder or a reference to a loop_* option.
+     *
+     * @param array<array-key, mixed> $nodes
+     */
+    private static function hasLoopContent(array $nodes): bool
+    {
+        $found = false;
+        array_walk_recursive($nodes, static function (mixed $value) use (&$found): void {
+            $found = $found || (is_string($value) && (
+                preg_match('/^\s*\{\{\s*loop\s*:/', $value) === 1
+                || str_starts_with((string) VariableRef::nameOf($value), 'loop_')
+            ));
+        });
+
+        return $found;
+    }
 }
diff --git a/src/Integrations/Divi/Pages/DiviWriteAbility.php b/src/Integrations/Divi/Pages/DiviWriteAbility.php
index 3da25a4..6052287 100644
--- a/src/Integrations/Divi/Pages/DiviWriteAbility.php
+++ b/src/Integrations/Divi/Pages/DiviWriteAbility.php
@@ -6,6 +6,10 @@ namespace LIT\MCP\Integrations\Divi\Pages;
 
 use LIT\MCP\Abilities\Ability;
 use LIT\MCP\Abilities\ToolResult;
+use LIT\MCP\Integrations\Divi\BlockTree\Block;
+use LIT\MCP\Integrations\Divi\BlockTree\NodeIndex;
+use LIT\MCP\Integrations\Divi\Compose\LoopContext;
+use LIT\MCP\Integrations\Divi\Compose\LoopScope;
 use LIT\MCP\Integrations\Divi\Release\DiviFeature;
 use LIT\MCP\Integrations\Divi\Release\FeatureSets;
 use LIT\MCP\Integrations\Divi\Release\RequiresDiviFeatures;
@@ -114,4 +118,22 @@ abstract class DiviWriteAbility implements Ability, RequiresDiviFeatures
     {
         return null;
     }
+
+    /**
+     * Ruling X3: the loop scope at $block – its nearest loop-enabled ancestor-or-self (LoopContext, X1); none at
+     * the top level. $newAttrs (node ID => attrs) replaces the stored attrs of nodes this call changes. The index
+     * is the tree loaded for this call, never a client value. Opaque blocks are never entered by NodeIndex, so one
+     * can only be $block itself – and every tool refuses to write into or onto it.
+     *
+     * @param array<string, array<string, mixed>> $newAttrs
+     */
+    protected static function loopAt(NodeIndex $index, ?Block $block, array $newAttrs = []): LoopScope
+    {
+        $chain = [];
+        for ($node = $block; $node !== null; $node = $index->parentBlock($node)) {
+            array_unshift($chain, $newAttrs[(string) $index->idOf($node)] ?? $node->attrs());
+        }
+
+        return LoopContext::fromChain($chain);
+    }
 }
diff --git a/tests/Support/DiviWriterFixture.php b/tests/Support/DiviWriterFixture.php
index 8a54352..750a6fd 100644
--- a/tests/Support/DiviWriterFixture.php
+++ b/tests/Support/DiviWriterFixture.php
@@ -92,7 +92,8 @@ final class DiviWriterFixture
     }
 
     /**
-     * The writer over the page of DiviFixtures::givenPost(), saving into $saved (see saver()).
+     * The writer over the page of DiviFixtures::givenPost(), saving into $saved (see saver()); $registry is the
+     * composition's dynamic content map (see composition()).
      *
      * @param list<string>    $saved
      * @param list<Throwable> $failures
@@ -104,7 +105,8 @@ final class DiviWriterFixture
         ?DiviPageLoader $loader = null,
         ?GlobalEdits $globals = null,
         ?ThemeBuilderEdits $themeBuilder = null,
-        ?SimilarSections $similar = null
+        ?SimilarSections $similar = null,
+        ?DynamicContentMap $registry = null
     ): DiviWriter {
         $design = self::designReader();
 
@@ -113,7 +115,7 @@ final class DiviWriterFixture
             self::saver($saved, $failures),
             self::log(),
             $design,
-            self::composition($design, $unfiltered),
+            self::composition($design, $unfiltered, $registry),
             $globals,
             $themeBuilder,
             $similar
diff --git a/tests/Unit/Integrations/Divi/Pages/DiviLoopWriteTest.php b/tests/Unit/Integrations/Divi/Pages/DiviLoopWriteTest.php
new file mode 100644
index 0000000..f28f89b
--- /dev/null
+++ b/tests/Unit/Integrations/Divi/Pages/DiviLoopWriteTest.php
@@ -0,0 +1,175 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Tests\Unit\Integrations\Divi\Pages;
+
+use LIT\MCP\Abilities\Rev;
+use LIT\MCP\Integrations\Divi\Compose\VariableRef;
+use LIT\MCP\Integrations\Divi\Pages\DynamicContentMap;
+use LIT\MCP\Tests\Support\DiviFixtures;
+use LIT\MCP\Tests\Support\DiviWriterFixture;
+use WP_Error;
+
+/**
+ * Ruling X3: lit/divi-insert, lit/divi-update and lit/divi-move use the loop scope of the node in the tree
+ * (LoopContext). The page: s0.r0.c0 runs a post loop (m0 shows loop_post_title, m1 is plain text, m2 runs its own
+ * term loop and shows loop_term_name), s0.r0.c1 a term loop, s0.r0.c2 no loop.
+ */
+final class DiviLoopWriteTest extends DiviWriteAbilityTestCase
+{
+    private const POST_LOOP = ['enable' => 'on', 'queryType' => 'post_types'];
+    private const TERM_LOOP = ['enable' => 'on', 'queryType' => 'post_taxonomies'];
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+        $this->original = self::page();
+        $this->post->post_content = $this->original;
+        $registry = self::registry();
+        $this->writer = DiviWriterFixture::writer(
+            $this->saved,
+            registry: new DynamicContentMap(static fn (int $postId): array => $registry)
+        );
+    }
+
+    /** DiviFixtures' registry plus the loop options these tests name (Divi 5.15.1 groups and fields). */
+    private static function registry(): array
+    {
+        $field = static fn (string $type): array => ['label' => 'x', 'type' => $type, 'default' => ''];
+        $common = ['before' => $field('text'), 'after' => $field('text'), 'loop_position' => $field('text')];
+        $option = static fn (string $id, string $group, array $fields): array => [
+            'id' => $id, 'label' => $id, 'type' => 'text', 'custom' => false, 'group' => $group, 'fields' => $fields,
+        ];
+
+        return DiviFixtures::dynamicContentRegistry() + [
+            'loop_post_date' => $option('loop_post_date', 'Loop', $common + [
+                'date_format' => $field('select'), 'custom_date_format' => $field('text'),
+            ]),
+            'loop_term_name' => $option('loop_term_name', 'Loop Terms', $common),
+        ];
+    }
+
+    /** @param array<string, mixed> $attrs */
+    private static function block(string $name, array $attrs, string $inner = ''): string
+    {
+        $json = (string) json_encode($attrs + ['builderVersion' => '5.2.1'], JSON_UNESCAPED_UNICODE);
+
+        return sprintf('<!-- wp:divi/%s %s -->%s<!-- /wp:divi/%s -->', $name, $json, $inner, $name);
+    }
+
+    /** @param array<string, string> $loop */
+    private static function loop(array $loop): array
+    {
+        return ['module' => ['advanced' => ['loop' => ['desktop' => ['value' => $loop]]]]];
+    }
+
+    private static function text(string $value): string
+    {
+        return self::block('text', ['content' => ['innerContent' => ['desktop' => ['value' => $value]]]]);
+    }
+
+    private static function page(): string
+    {
+        $title = VariableRef::serialize('content', 'loop_post_title', ['before' => '', 'after' => '']);
+        $term = VariableRef::serialize('content', 'loop_term_name', ['before' => '', 'after' => '']);
+        $own = self::block('text', self::loop(self::TERM_LOOP) + [
+            'content' => ['innerContent' => ['desktop' => ['value' => $term]]],
+        ]);
+
+        return '<!-- wp:divi/placeholder -->' . self::block('section', [], self::block('row', [], implode('', [
+            self::block('column', self::loop(self::POST_LOOP), self::text($title) . self::text('<p>Fest</p>') . $own),
+            self::block('column', self::loop(self::TERM_LOOP), self::text('<p>Term</p>')),
+            self::block('column', [], self::text('<p>Ohne</p>')),
+        ]))) . '<!-- /wp:divi/placeholder -->';
+    }
+
+    /** @param array<string, mixed> $input */
+    private function insertInto(string $parent, array $input): mixed
+    {
+        return $this->insert()->execute(
+            ['post_id' => 7, 'tree_rev' => $this->currentRev(), 'parent' => $parent] + $input
+        );
+    }
+
+    /** @param list<array<string, mixed>> $changes */
+    private function changeAll(array $changes): mixed
+    {
+        return $this->update()->execute(['post_id' => 7, 'tree_rev' => $this->currentRev(), 'changes' => $changes]);
+    }
+
+    /** @param array<string, mixed> $input */
+    private function moveNode(array $input): mixed
+    {
+        return $this->move()->execute(['post_id' => 7, 'tree_rev' => $this->currentRev()] + $input);
+    }
+
+    /** tree_rev of what the page holds now (the saver puts every saved content on the post). */
+    private function currentRev(): string
+    {
+        return Rev::of((string) $this->post->post_content);
+    }
+
+    private static function problems(mixed $error): string
+    {
+        self::assertInstanceOf(WP_Error::class, $error);
+
+        return implode(' | ', self::errorFields($error));
+    }
+
+    public function testInsertUsesTheLoopOfTheTargetParent(): void
+    {
+        $result = $this->insertInto('s0.r0.c0', ['nodes' => [
+            ['type' => 'text', 'content' => '{{loop:post_date}}'],
+            ['type' => 'text', 'content' => '{{loop:post_title}}'],
+        ]]);
+
+        self::assertTrue($result['ok'], (string) json_encode($result));
+        $date = VariableRef::serialize('content', 'loop_post_date', ['before' => '', 'after' => '']);
+        self::assertStringContainsString(str_replace('"', '\\' . 'u0022', $date), $this->saved[0]);
+
+        $term = $this->insertInto('s0.r0.c1', ['nodes' => [['type' => 'text', 'content' => '{{loop:term_name}}']]]);
+        self::assertTrue($term['ok'], (string) json_encode($term));
+    }
+
+    public function testInsertRefusesLoopContentOutsideALoopOrOfAnotherKind(): void
+    {
+        $outside = $this->insertInto('s0.r0.c2', ['nodes' => [['type' => 'text', 'content' => '{{loop:post_date}}']]]);
+        self::assertStringContainsString('braucht eine Divi-Schleife', self::problems($outside));
+
+        $term = $this->insertInto('s0.r0.c1', ['nodes' => [['type' => 'text', 'content' => '{{loop:post_date}}']]]);
+        $wrongKind = self::problems($term);
+        self::assertStringContainsString('passt nicht zur Schleife dieses Elements (Typ: Terme)', $wrongKind);
+
+        $topLevel = $this->insert()->execute([
+            'post_id' => 7,
+            'tree_rev' => $this->currentRev(),
+            'nodes' => [['type' => 'section', 'modules' => [['type' => 'text', 'content' => '{{loop:post_date}}']]]],
+        ]);
+        self::assertStringContainsString('braucht eine Divi-Schleife', self::problems($topLevel));
+        self::assertSame([], $this->saved);
+    }
+
+    /**
+     * Ruling X3, fail closed: a loop a new node of this call switches on counts only once it is saved – loop
+     * content in the same call is refused even where the parent's loop would let it pass (a term loop inside the
+     * post loop c0 would otherwise get post content: Divi reads the post with the term's ID).
+     */
+    public function testANewLoopInTheSameCallIsRefusedWithLoopContent(): void
+    {
+        $ownLoop = ['module.advanced.loop' => ['desktop' => self::TERM_LOOP]];
+
+        foreach (['s0.r0.c0' => '{{loop:post_title}}', 's0.r0.c2' => '{{loop:term_name}}'] as $parent => $content) {
+            $refused = $this->insertInto($parent, ['nodes' => [
+                ['type' => 'text', 'attrs' => $ownLoop, 'content' => $content],
+            ]]);
+            self::assertStringContainsString('erst nach dem Speichern', self::problems($refused), $parent);
+        }
+        self::assertSame([], $this->saved);
+
+        $withoutLoopContent = $this->insertInto('s0.r0.c2', ['nodes' => [
+            ['type' => 'text', 'attrs' => $ownLoop, 'content' => '<p>Liste</p>'],
+        ]]);
+        self::assertTrue($withoutLoopContent['ok'], (string) json_encode($withoutLoopContent));
+    }
+}