diff --git a/google/cloud/documentai_toolbox/wrappers/document.py b/google/cloud/documentai_toolbox/wrappers/document.py
index e90dc3a..dd84ffb 100644
--- a/google/cloud/documentai_toolbox/wrappers/document.py
+++ b/google/cloud/documentai_toolbox/wrappers/document.py
@@ -732,6 +732,19 @@ def convert_document_to_annotate_file_response(self) -> AnnotateFileResponse:
         """
         return _convert_to_vision_annotate_file_response(self.text, self.pages)
 
+    def convert_document_to_annotate_file_json_response(self) -> str:
+        r"""Convert OCR data from Document.proto to JSON str of AnnotateFileResponse for Vision API.
+
+        Args:
+            None.
+        Returns:
+            str:
+                JSON string of TextAnnotations.
+        """
+        return AnnotateFileResponse.to_json(
+            _convert_to_vision_annotate_file_response(self.text, self.pages)
+        )
+
     def export_images(
         self, output_path: str, output_file_prefix: str, output_file_extension: str
     ) -> List[str]:
diff --git a/scripts/readme-gen/readme_gen.py b/scripts/readme-gen/readme_gen.py
index 91b5967..b533840 100644
--- a/scripts/readme-gen/readme_gen.py
+++ b/scripts/readme-gen/readme_gen.py
@@ -33,17 +33,17 @@
     autoescape=True,
 )
 
-README_TMPL = jinja_env.get_template('README.tmpl.rst')
+README_TMPL = jinja_env.get_template("README.tmpl.rst")
 
 
 def get_help(file):
-    return subprocess.check_output(['python', file, '--help']).decode()
+    return subprocess.check_output(["python", file, "--help"]).decode()
 
 
 def main():
     parser = argparse.ArgumentParser()
-    parser.add_argument('source')
-    parser.add_argument('--destination', default='README.rst')
+    parser.add_argument("source")
+    parser.add_argument("--destination", default="README.rst")
 
     args = parser.parse_args()
 
@@ -51,9 +51,9 @@ def main():
     root = os.path.dirname(source)
     destination = os.path.join(root, args.destination)
 
-    jinja_env.globals['get_help'] = get_help
+    jinja_env.globals["get_help"] = get_help
 
-    with io.open(source, 'r') as f:
+    with io.open(source, "r") as f:
         config = yaml.load(f)
 
     # This allows get_help to execute in the right directory.
@@ -61,9 +61,9 @@ def main():
 
     output = README_TMPL.render(config)
 
-    with io.open(destination, 'w') as f:
+    with io.open(destination, "w") as f:
         f.write(output)
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()
diff --git a/tests/unit/test_document.py b/tests/unit/test_document.py
index 38b03d4..7839f4e 100644
--- a/tests/unit/test_document.py
+++ b/tests/unit/test_document.py
@@ -536,6 +536,19 @@ def test_convert_document_to_annotate_file_response():
     assert actual == expected
 
 
+def test_convert_document_to_annotate_file_json_response():
+    doc = document.Document.from_document_path(
+        document_path="tests/unit/resources/0/toolbox_invoice_test-0.json"
+    )
+
+    actual = doc.convert_document_to_annotate_file_json_response()
+
+    with open("tests/unit/resources/toolbox_invoice_test-0-vision.json", "r") as f:
+        expected = f.read()
+
+    assert actual == expected
+
+
 def test_export_images(get_bytes_images_mock):
     doc = document.Document.from_gcs(
         gcs_bucket_name="test-directory", gcs_prefix="documentai/output/123456789/0"