diff --git a/src/Annotations/AbstractAnnotation.php b/src/Annotations/AbstractAnnotation.php
index de5407cae..e832a7429 100644
--- a/src/Annotations/AbstractAnnotation.php
+++ b/src/Annotations/AbstractAnnotation.php
@@ -8,6 +8,7 @@
 
 use OpenApi\Context;
 use OpenApi\Generator;
+use OpenApi\Annotations as OA;
 use OpenApi\Util;
 use Symfony\Component\Yaml\Yaml;
 
@@ -566,7 +567,7 @@ public function identity(): string
     /**
      * Find matching nested details.
      *
-     * @param string $class the class to match
+     * @param class-string $class the class to match
      *
      * @return null|object key/value object or `null`
      */
@@ -587,6 +588,25 @@ public static function matchNested(string $class)
         return null;
     }
 
+    /**
+     * Match the annotation root.
+     *
+     * @param class-string $rootClass the root class to match
+     */
+    public function isRoot(string $rootClass): bool
+    {
+        $parent = get_class($this);
+
+        // only consider the immediate OpenApi parent
+        do {
+            if ($parent == $rootClass) {
+                return true;
+            }
+        } while (0 !== strpos($parent, 'OpenApi\\Annotations\\')  && $parent = get_parent_class($parent));
+
+        return false;
+    }
+
     /**
      * Helper for generating the identity().
      */
diff --git a/src/Processors/AugmentSchemas.php b/src/Processors/AugmentSchemas.php
index 1b32f6972..f6147f627 100644
--- a/src/Processors/AugmentSchemas.php
+++ b/src/Processors/AugmentSchemas.php
@@ -8,7 +8,6 @@
 
 use OpenApi\Analysis;
 use OpenApi\Annotations as OA;
-use OpenApi\Attributes as OAT;
 use OpenApi\Context;
 use OpenApi\Generator;
 
@@ -21,8 +20,13 @@ class AugmentSchemas
 {
     public function __invoke(Analysis $analysis)
     {
-        /** @var OA\Schema $schema */
-        foreach ($analysis->getAnnotationsOfType([OA\Schema::class, OAT\Schema::class], true) as $schema) {
+        /** @var OA\Schema[] $schemas */
+        $schemas = $analysis->getAnnotationsOfType(OA\Schema::class);
+
+        foreach ($schemas as $schema) {
+            if (!$schema->isRoot(OA\Schema::class)) {
+                continue;
+            }
             if (Generator::isDefault($schema->schema)) {
                 if ($schema->_context->is('class')) {
                     $schema->schema = $schema->_context->class;
@@ -36,9 +40,6 @@ public function __invoke(Analysis $analysis)
             }
         }
 
-        /** @var OA\Schema[] $schemas */
-        $schemas = $analysis->getAnnotationsOfType(OA\Schema::class);
-
         // Merge unmerged @OA\Property annotations into the @OA\Schema of the class
         $unmergedProperties = $analysis->unmerged()->getAnnotationsOfType(OA\Property::class);
         foreach ($unmergedProperties as $property) {
diff --git a/tests/Annotations/AbstractAnnotationTest.php b/tests/Annotations/AbstractAnnotationTest.php
index 9730238ca..4ab7da5db 100644
--- a/tests/Annotations/AbstractAnnotationTest.php
+++ b/tests/Annotations/AbstractAnnotationTest.php
@@ -6,9 +6,7 @@
 
 namespace OpenApi\Tests\Annotations;
 
-use OpenApi\Annotations\Get;
-use OpenApi\Annotations\Parameter;
-use OpenApi\Annotations\Schema;
+use OpenApi\Annotations as OA;
 use OpenApi\Generator;
 use OpenApi\Tests\OpenApiTestCase;
 
@@ -112,12 +110,12 @@ public function testTypeValidation(): void
 
     public function nestedMatches(): iterable
     {
-        $parameterMatch = (object) ['key' => Parameter::class, 'value' => ['parameters']];
+        $parameterMatch = (object) ['key' => OA\Parameter::class, 'value' => ['parameters']];
 
         return [
             'unknown' => [self::class, null],
-            'simple-match' => [Parameter::class, $parameterMatch],
-            'invalid-annotation' => [Schema::class, null],
+            'simple-match' => [OA\Parameter::class, $parameterMatch],
+            'invalid-annotation' => [OA\Schema::class, null],
             'sub-annotation' => [SubParameter::class, $parameterMatch],
             'sub-sub-annotation' => [SubSubParameter::class, $parameterMatch],
             'sub-invalid' => [SubSchema::class, null],
@@ -129,7 +127,7 @@ public function nestedMatches(): iterable
      */
     public function testMatchNested(string $class, $expected): void
     {
-        $this->assertEquals($expected, Get::matchNested($class));
+        $this->assertEquals($expected, OA\Get::matchNested($class));
     }
 
     public function testDuplicateOperationIdValidation(): void
@@ -140,13 +138,20 @@ public function testDuplicateOperationIdValidation(): void
         $this->assertOpenApiLogEntryContains('operationId must be unique. Duplicate value found: "getItem"');
         $this->assertFalse($analysis->validate());
     }
+
+    public function testIsRoot(): void
+    {
+        $this->assertTrue((new OA\AdditionalProperties([]))->isRoot(OA\AdditionalProperties::class));
+        $this->assertFalse((new OA\AdditionalProperties([]))->isRoot(OA\Schema::class));
+        $this->assertTrue((new SubSchema([]))->isRoot(OA\Schema::class));
+    }
 }
 
-class SubSchema extends Schema
+class SubSchema extends OA\Schema
 {
 }
 
-class SubParameter extends Parameter
+class SubParameter extends OA\Parameter
 {
 }
 
diff --git a/tests/Fixtures/Scratch/CustomAttributeSchema.php b/tests/Fixtures/Scratch/CustomAttributeSchema.php
new file mode 100644
index 000000000..f2060314f
--- /dev/null
+++ b/tests/Fixtures/Scratch/CustomAttributeSchema.php
@@ -0,0 +1,32 @@
+<?php declare(strict_types=1);
+
+/**
+ * @license Apache 2.0
+ */
+
+namespace OpenApi\Tests\Fixtures\Scratch;
+
+use OpenApi\Attributes as OAT;
+
+#[\Attribute(\Attribute::TARGET_CLASS | \Attribute::TARGET_METHOD | \Attribute::TARGET_PROPERTY)]
+class CustomAttributeSchema extends OAT\Schema
+{
+}
+
+#[CustomAttributeSchema()]
+class MyClass
+{
+}
+
+#[OAT\Info(
+    title: 'Custom Attribute Schema Scratch',
+    version: '1.0'
+)]
+#[OAT\Get(
+    path: '/api/endpoint',
+    description: 'An endpoint',
+    responses: [new OAT\Response(response: 200, description: 'OK')]
+)]
+class CustomAttributeSchemaEndpoint
+{
+}
diff --git a/tests/Fixtures/Scratch/CustomAttributeSchema.yaml b/tests/Fixtures/Scratch/CustomAttributeSchema.yaml
new file mode 100644
index 000000000..6f3b2b734
--- /dev/null
+++ b/tests/Fixtures/Scratch/CustomAttributeSchema.yaml
@@ -0,0 +1,14 @@
+openapi: 3.0.0
+info:
+  title: 'Custom Attribute Schema Scratch'
+  version: '1.0'
+paths:
+  /api/endpoint:
+    get:
+      description: 'An endpoint'
+      responses:
+        '200':
+          description: OK
+components:
+  schemas:
+    MyClass: {  }
diff --git a/tests/Fixtures/Scratch/MergeTraits.php b/tests/Fixtures/Scratch/MergeTraits.php
index 57a8b704c..5a99f49c6 100644
--- a/tests/Fixtures/Scratch/MergeTraits.php
+++ b/tests/Fixtures/Scratch/MergeTraits.php
@@ -74,6 +74,6 @@ class Address extends Model
  *     )
  * )
  */
-class Endpoint
+class MergeTraitsEndpoint
 {
 }
diff --git a/tests/Fixtures/Scratch/ParameterContent.php b/tests/Fixtures/Scratch/ParameterContent.php
index 9d9029f62..2d3889342 100644
--- a/tests/Fixtures/Scratch/ParameterContent.php
+++ b/tests/Fixtures/Scratch/ParameterContent.php
@@ -32,6 +32,6 @@
     ],
     responses: [new OAT\Response(response: 200, description: 'OK')]
 )]
-class Endpoint
+class ParameterContentEndpoint
 {
 }