diff --git a/.gitignore b/.gitignore
index fb051901..dea44278 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,7 +11,6 @@
 /build/out
 /build/*.phar
 /tests/statics/index.*
-src/Michelf/*
 src/.gitignore
 vendor/**
 
diff --git a/phpdraft b/phpdraft
index 90ea0f77..a1468992 100755
--- a/phpdraft
+++ b/phpdraft
@@ -28,6 +28,7 @@ try
         ->opt('help:h', 'This help text', false)
         ->opt('version:v', 'Print the version for PHPDraft.', false)
         ->opt('file:f', 'Specifies the file to parse.', false)
+        ->opt('openapi:a', 'Output location for an OpenAPI file.', false)
         ->opt('yes:y', 'Always accept using the online mode.', false, 'bool')
         ->opt('online:o', 'Always use the online mode.', false, 'bool')
         ->opt('template:t', 'Specifies the template to use. (defaults to \'default\').', false)
@@ -90,6 +91,11 @@ try
         $data = json_decode($json_string);
     }
 
+    if (isset($args['openapi'])) {
+        $openapi = ParserFactory::getOpenAPI()->init($data);
+        $openapi->write($args['openapi']);
+    }
+
     $html          = ParserFactory::getJson()->init($data);
     $name          = 'PHPD_SORT_' . strtoupper($args->getOpt('sort', ''));
     $html->sorting = Sorting::${$name} ?? Sorting::PHPD_SORT_NONE->value;
diff --git a/src/PHPDraft/Model/HTTPRequest.php b/src/PHPDraft/Model/HTTPRequest.php
index c551184f..1b88318c 100644
--- a/src/PHPDraft/Model/HTTPRequest.php
+++ b/src/PHPDraft/Model/HTTPRequest.php
@@ -43,7 +43,7 @@ class HTTPRequest implements Comparable
      *
      * @var string
      */
-    public string $description;
+    public string $description = '';
 
     /**
      * Parent class.
diff --git a/src/PHPDraft/Model/Transition.php b/src/PHPDraft/Model/Transition.php
index 8158f94e..2d488197 100644
--- a/src/PHPDraft/Model/Transition.php
+++ b/src/PHPDraft/Model/Transition.php
@@ -23,9 +23,9 @@ class Transition extends HierarchyElement
     /**
      * HTTP method used.
      *
-     * @var string
+     * @var string|null
      */
-    public string $method;
+    public ?string $method = NULL;
 
     /**
      * URI.
diff --git a/src/PHPDraft/Out/BaseTemplateRenderer.php b/src/PHPDraft/Out/BaseTemplateRenderer.php
index b8052cad..5532a169 100644
--- a/src/PHPDraft/Out/BaseTemplateRenderer.php
+++ b/src/PHPDraft/Out/BaseTemplateRenderer.php
@@ -24,36 +24,21 @@ abstract class BaseTemplateRenderer
      * @var int
      */
     public int $sorting;
+
     /**
-     * CSS Files to load.
-     *
-     * @var string[]
-     */
-    public array $css = [];
-    /**
-     * JS Files to load.
-     *
-     * @var string[]
-     */
-    public array $js = [];
-    /**
-     * The image to use as a logo.
-     *
-     * @var string|null
-     */
-    protected ?string $image = null;
-    /**
-     * The template file to load.
+     * JSON representation of an API Blueprint.
      *
-     * @var string
+     * @var object
      */
-    protected string $template;
+    protected object $object;
+
     /**
      * The base data of the API.
      *
      * @var array<string, mixed>
      */
-    protected array $base_data;
+    protected array $base_data = [];
+
     /**
      * JSON object of the API blueprint.
      *
@@ -66,4 +51,39 @@ abstract class BaseTemplateRenderer
      * @var ObjectStructureElement[]
      */
     protected array $base_structures = [];
+
+    /**
+     * Parse base data
+     *
+     * @param object $object
+     */
+    protected function parse_base_data(object $object): void
+    {
+        //Prepare base data
+        if (!is_array($object->content[0]->content)) {
+            return;
+        }
+
+        $this->base_data['TITLE'] = $object->content[0]->meta->title->content ?? '';
+
+        foreach ($object->content[0]->attributes->metadata->content as $meta) {
+            $this->base_data[$meta->content->key->content] = $meta->content->value->content;
+        }
+
+        foreach ($object->content[0]->content as $value) {
+            if ($value->element === 'copy') {
+                $this->base_data['DESC'] = $value->content;
+                continue;
+            }
+
+            $cat = new Category();
+            $cat = $cat->parse($value);
+
+            if (($value->meta->classes->content[0]->content ?? null) === 'dataStructures') {
+                $this->base_structures = array_merge($this->base_structures, $cat->structures);
+            } else {
+                $this->categories[] = $cat;
+            }
+        }
+    }
 }
diff --git a/src/PHPDraft/Out/TemplateRenderer.php b/src/PHPDraft/Out/TemplateRenderer.php
deleted file mode 100644
index 7ad6a025..00000000
--- a/src/PHPDraft/Out/TemplateRenderer.php
+++ /dev/null
@@ -1,231 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-/**
- * This file contains the TemplateGenerator.php.
- *
- * @package PHPDraft\Out
- *
- * @author  Sean Molenaar<sean@seanmolenaar.eu>
- */
-
-namespace PHPDraft\Out;
-
-use Lukasoppermann\Httpstatus\Httpstatus;
-use PHPDraft\Model\Category;
-use PHPDraft\Model\Elements\ArrayStructureElement;
-use PHPDraft\Model\Elements\ElementStructureElement;
-use PHPDraft\Model\Elements\EnumStructureElement;
-use PHPDraft\Model\Elements\ObjectStructureElement;
-use PHPDraft\Parse\ExecutionException;
-use Twig\Environment;
-use Twig\Extra\Markdown\DefaultMarkdown;
-use Twig\Extra\Markdown\MarkdownExtension;
-use Twig\Extra\Markdown\MarkdownRuntime;
-use Twig\Loader\FilesystemLoader;
-use Twig\RuntimeLoader\RuntimeLoaderInterface;
-use Twig\TwigFilter;
-use Twig\TwigTest;
-
-class TemplateRenderer extends BaseTemplateRenderer
-{
-    /**
-     * TemplateGenerator constructor.
-     *
-     * @param string      $template Name of the template to load
-     * @param string|null $image    Image to use as Logo
-     */
-    public function __construct(string $template, ?string $image)
-    {
-        $template_parts             = explode('__', $template);
-        $this->template             = $template_parts[0];
-        $this->base_data['COLOR_1'] = $template_parts[1] ?? 'green';
-        $this->base_data['COLOR_2'] = $template_parts[2] ?? 'light_green';
-        $this->image                = $image;
-        $this->sorting              = Sorting::PHPD_SORT_NONE->value;
-    }
-
-    /**
-     * Pre-parse objects needed and print HTML.
-     *
-     * @param object $object JSON to parse from
-     *
-     * @return string
-     *
-     * @throws ExecutionException When template is not found
-     *
-     * @throws \Twig\Error\LoaderError
-     * @throws \Twig\Error\RuntimeError
-     * @throws \Twig\Error\SyntaxError
-     */
-    public function get(object $object): string
-    {
-        $include = $this->find_include_file($this->template, 'twig', false);
-        if ($include === null) {
-            throw new ExecutionException("Couldn't find template '$this->template'", 1);
-        }
-
-        $this->parse_base_data($object);
-
-        if (Sorting::sortStructures($this->sorting)) {
-            ksort($this->base_structures);
-        }
-
-        if (Sorting::sortServices($this->sorting)) {
-            usort($this->categories, fn($a, $b) => strcmp($a->title, $b->title));
-            foreach ($this->categories as $category) {
-                usort($category->children, fn($a, $b)=> strcmp($a->title, $b->title));
-            }
-        }
-
-        $loader   = new FilesystemLoader([]);
-        $loader->addPath(stream_resolve_include_path(dirname($include)));
-        $loader->addPath(stream_resolve_include_path(dirname($this->find_include_file('default', 'twig'))));
-
-        $twig     = TwigFactory::get($loader);
-        $template = $twig->load('main.twig');
-
-        $extras = array_filter(
-            $this->base_data,
-            fn($value) => !in_array($value, ['HOST', 'TITLE', 'ALT_HOST', 'FORMAT', 'DESC', 'COLOR_1', 'COLOR_2'], true),
-            ARRAY_FILTER_USE_KEY
-        );
-        $extras['host'] = $this->base_data['HOST'] ?? null;
-
-        return $template->render([
-            'data' => $this->base_data,
-            'extra_data' => $extras,
-            'structures' => $this->base_structures,
-            'categories' => $this->categories,
-            'js' => $this->js,
-            'css' => $this->css,
-            'image' => $this->image,
-            'template_css' => file_get_contents($this->find_include_file($this->template, 'css'), true),
-            'template_js' => file_get_contents($this->find_include_file($this->template, 'js'), true),
-        ]);
-    }
-
-    /**
-     * Parse base data
-     *
-     * @param object $object
-     */
-    private function parse_base_data(object $object): void
-    {
-        //Prepare base data
-        if (!is_array($object->content[0]->content)) {
-            return;
-        }
-
-        $this->base_data['TITLE'] = $object->content[0]->meta->title->content ?? '';
-
-        foreach ($object->content[0]->attributes->metadata->content as $meta) {
-            $this->base_data[$meta->content->key->content] = $meta->content->value->content;
-        }
-
-        foreach ($object->content[0]->content as $value) {
-            if ($value->element === 'copy') {
-                $this->base_data['DESC'] = $value->content;
-                continue;
-            }
-
-            $cat = new Category();
-            $cat = $cat->parse($value);
-
-            if (($value->meta->classes->content[0]->content ?? null) === 'dataStructures') {
-                $this->base_structures = array_merge($this->base_structures, $cat->structures);
-            } else {
-                $this->categories[] = $cat;
-            }
-        }
-    }
-
-    /**
-     * Get the path to a file to include.
-     *
-     * @param string $template  The name of the template to include
-     * @param string $extension Extension of the file to include
-     *
-     * @return null|string File path or null if not found
-     */
-    public function find_include_file(string $template, string $extension = 'twig', bool $fallback = true): ?string
-    {
-        $includes = [
-            'templates' . DIRECTORY_SEPARATOR . $template . DIRECTORY_SEPARATOR . $template . ".{$extension}",
-            'templates' . DIRECTORY_SEPARATOR . $template . DIRECTORY_SEPARATOR . 'main' . ".{$extension}",
-            'templates' . DIRECTORY_SEPARATOR . $template . ".{$extension}",
-            $template . DIRECTORY_SEPARATOR . $template . ".{$extension}",
-            $template . ".{$extension}",
-            'PHPDraft/Out/HTML/' . $template . DIRECTORY_SEPARATOR . $template . ".{$extension}",
-            'PHPDraft/Out/HTML/' . $template . DIRECTORY_SEPARATOR . 'main' . ".{$extension}",
-        ];
-        foreach ($includes as $include) {
-            if (!stream_resolve_include_path($include)) {
-                continue;
-            }
-            return $include;
-        }
-
-        if (in_array($extension, ['twig', 'js', 'css'], true) && $template !== 'default' && $fallback === true) {
-            return $this->find_include_file('default', $extension);
-        }
-
-        return null;
-    }
-
-    /**
-     * Get an icon for a specific HTTP Method.
-     *
-     * @param string $method HTTP method
-     *
-     * @return string class to represent the HTTP Method
-     */
-    public static function get_method_icon(string $method): string
-    {
-        $class = ['fas', strtoupper($method)];
-        $class[] = match (strtoupper($method)) {
-            'POST' => 'fa-plus-square',
-            'PUT' => 'fa-pen-square',
-            'GET' => 'fa-arrow-circle-down',
-            'DELETE' => 'fa-minus-square',
-            'HEAD' => 'fa-info',
-            'CONNECT' => 'fa-ethernet',
-            'OPTIONS' => 'fa-sliders-h',
-            'TRACE' => 'fa-route',
-            'PATCH' => 'fa-band-aid',
-            default => ''
-        };
-
-        return trim(join(' ', $class));
-    }
-
-    /**
-     * Get a bootstrap class to represent the HTTP return code range.
-     *
-     * @param int $response HTTP return code
-     *
-     * @return string Class to use
-     */
-    public static function get_response_status(int $response): string
-    {
-        $http = new Httpstatus();
-        return match ($http->getResponseClass($response)) {
-            Httpstatus::CLASS_SUCCESS => 'text-success',
-            Httpstatus::CLASS_REDIRECTION => 'text-warning',
-            default => 'text-error',
-        };
-    }
-
-    /**
-     * Strip spaces from links to objects.
-     *
-     * @param string $key key with potential spaces
-     *
-     * @return string key without spaces
-     */
-    public static function strip_link_spaces(string $key): string
-    {
-        return str_replace(' ', '-', strtolower($key));
-    }
-}
diff --git a/src/PHPDraft/Out/Tests/TemplateRendererTest.php b/src/PHPDraft/Out/Tests/TemplateRendererTest.php
index 72863cad..c47fb1c5 100644
--- a/src/PHPDraft/Out/Tests/TemplateRendererTest.php
+++ b/src/PHPDraft/Out/Tests/TemplateRendererTest.php
@@ -10,17 +10,17 @@
 namespace PHPDraft\Out\Tests;
 
 use Lunr\Halo\LunrBaseTest;
-use PHPDraft\Out\TemplateRenderer;
+use PHPDraft\Out\HtmlTemplateRenderer;
 
 /**
  * Class TemplateGeneratorTest
  *
- * @covers \PHPDraft\Out\TemplateRenderer
+ * @covers \PHPDraft\Out\HtmlTemplateRenderer
  */
 class TemplateRendererTest extends LunrBaseTest
 {
     /**
-     * @var TemplateRenderer
+     * @var HtmlTemplateRenderer
      */
     protected $class;
 
@@ -30,14 +30,14 @@ class TemplateRendererTest extends LunrBaseTest
      */
     public function setUp(): void
     {
-        $this->class      = new TemplateRenderer('default', 'none');
-        $this->reflection = new \ReflectionClass('PHPDraft\Out\TemplateRenderer');
+        $this->class      = new HtmlTemplateRenderer('default', 'none');
+        $this->reflection = new \ReflectionClass('PHPDraft\Out\HtmlTemplateRenderer');
     }
 
     /**
      * Test if the value the class is initialized with is correct
      *
-     * @covers \PHPDraft\Out\TemplateRenderer
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer
      */
     public function testSetupCorrectly(): void
     {
@@ -48,7 +48,7 @@ public function testSetupCorrectly(): void
     /**
      * Test if the value the class is initialized with is correct
      *
-     * @covers \PHPDraft\Out\TemplateRenderer::strip_link_spaces
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::strip_link_spaces
      */
     public function testStripSpaces(): void
     {
@@ -81,11 +81,11 @@ public static function responseStatusProvider(): array
      * @param int    $code HTTP code
      * @param string $text Class to return
      *
-     * @covers \PHPDraft\Out\TemplateRenderer::get_response_status
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::get_response_status
      */
     public function testResponseStatus(int $code, string $text): void
     {
-        $return = TemplateRenderer::get_response_status($code);
+        $return = HtmlTemplateRenderer::get_response_status($code);
         $this->assertEquals($text, $return);
     }
 
@@ -120,18 +120,18 @@ public static function requestMethodProvider(): array
      * @param string $method HTTP Method
      * @param string $text Class to return
      *
-     * @covers \PHPDraft\Out\TemplateRenderer::get_method_icon
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::get_method_icon
      */
     public function testRequestMethod(string $method, string $text): void
     {
-        $return = TemplateRenderer::get_method_icon($method);
+        $return = HtmlTemplateRenderer::get_method_icon($method);
         $this->assertEquals($text, $return);
     }
 
     /**
      * Test if the value the class is initialized with is correct
      *
-     * @covers \PHPDraft\Out\TemplateRenderer::find_include_file
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::find_include_file
      */
     public function testIncludeFileDefault(): void
     {
@@ -142,7 +142,7 @@ public function testIncludeFileDefault(): void
     /**
      * Test if the value the class is initialized with is correct
      *
-     * @covers \PHPDraft\Out\TemplateRenderer::find_include_file
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::find_include_file
      */
     public function testIncludeFileFallback(): void
     {
@@ -153,7 +153,7 @@ public function testIncludeFileFallback(): void
     /**
      * Test if the value the class is initialized with is correct
      *
-     * @covers \PHPDraft\Out\TemplateRenderer::find_include_file
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::find_include_file
      */
     public function testIncludeFileNone(): void
     {
@@ -164,7 +164,7 @@ public function testIncludeFileNone(): void
     /**
      * Test if the value the class is initialized with is correct
      *
-     * @covers \PHPDraft\Out\TemplateRenderer::find_include_file
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::find_include_file
      */
     public function testIncludeFileSingle(): void
     {
@@ -176,7 +176,7 @@ public function testIncludeFileSingle(): void
     /**
      * Test if the value the class is initialized with is correct
      *
-     * @covers \PHPDraft\Out\TemplateRenderer::find_include_file
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::find_include_file
      */
     public function testIncludeFileMultiple(): void
     {
@@ -192,7 +192,7 @@ public function testIncludeFileMultiple(): void
     }
 
     /**
-     * @covers \PHPDraft\Out\TemplateRenderer::get
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::get
      */
     public function testGetTemplateFailsEmpty(): void
     {
@@ -205,7 +205,7 @@ public function testGetTemplateFailsEmpty(): void
     }
 
     /**
-     * @covers \PHPDraft\Out\TemplateRenderer::get
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::get
      * @group twig
      */
     public function testGetTemplate(): void
@@ -216,7 +216,7 @@ public function testGetTemplate(): void
     }
 
     /**
-     * @covers \PHPDraft\Out\TemplateRenderer::get
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::get
      * @group twig
      */
     public function testGetTemplateSorting(): void
@@ -228,7 +228,7 @@ public function testGetTemplateSorting(): void
     }
 
     /**
-     * @covers \PHPDraft\Out\TemplateRenderer::get
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::get
      * @group twig
      */
     public function testGetTemplateMetaData(): void
@@ -247,7 +247,7 @@ public function testGetTemplateMetaData(): void
     }
 
     /**
-     * @covers \PHPDraft\Out\TemplateRenderer::get
+     * @covers \PHPDraft\Out\HtmlTemplateRenderer::get
      * @group twig
      */
     public function testGetTemplateCategories(): void
diff --git a/src/PHPDraft/Out/TwigFactory.php b/src/PHPDraft/Out/TwigFactory.php
index 725cbe89..102ed100 100644
--- a/src/PHPDraft/Out/TwigFactory.php
+++ b/src/PHPDraft/Out/TwigFactory.php
@@ -25,9 +25,9 @@ public static function get(LoaderInterface $loader): Environment
     {
         $twig = new Environment($loader);
 
-        $twig->addFilter(new TwigFilter('method_icon', fn(string $string) => TemplateRenderer::get_method_icon($string)));
-        $twig->addFilter(new TwigFilter('strip_link_spaces', fn(string $string) => TemplateRenderer::strip_link_spaces($string)));
-        $twig->addFilter(new TwigFilter('response_status', fn(string $string) => TemplateRenderer::get_response_status((int) $string)));
+        $twig->addFilter(new TwigFilter('method_icon', fn(string $string) => HtmlTemplateRenderer::get_method_icon($string)));
+        $twig->addFilter(new TwigFilter('strip_link_spaces', fn(string $string) => HtmlTemplateRenderer::strip_link_spaces($string)));
+        $twig->addFilter(new TwigFilter('response_status', fn(string $string) => HtmlTemplateRenderer::get_response_status((int) $string)));
         $twig->addFilter(new TwigFilter('status_reason', fn(int $code) => (new Httpstatus())->getReasonPhrase($code)));
         $twig->addFilter(new TwigFilter('minify_css', function (string $string) {
             $minify =  new Css();
diff --git a/src/PHPDraft/Parse/BaseHtmlGenerator.php b/src/PHPDraft/Parse/BaseHtmlGenerator.php
index ab3e25b7..37d750cf 100644
--- a/src/PHPDraft/Parse/BaseHtmlGenerator.php
+++ b/src/PHPDraft/Parse/BaseHtmlGenerator.php
@@ -12,8 +12,6 @@
 
 namespace PHPDraft\Parse;
 
-use PHPDraft\Out\BaseTemplateRenderer;
-use stdClass;
 use \Stringable;
 
 abstract class BaseHtmlGenerator implements Stringable
diff --git a/src/PHPDraft/Parse/HtmlGenerator.php b/src/PHPDraft/Parse/HtmlGenerator.php
index 3dc813ce..b8a1e6a5 100644
--- a/src/PHPDraft/Parse/HtmlGenerator.php
+++ b/src/PHPDraft/Parse/HtmlGenerator.php
@@ -12,7 +12,7 @@
 
 namespace PHPDraft\Parse;
 
-use PHPDraft\Out\TemplateRenderer;
+use PHPDraft\Out\HtmlTemplateRenderer;
 
 /**
  * Class HtmlGenerator.
@@ -36,7 +36,7 @@ class HtmlGenerator extends BaseHtmlGenerator
      */
     public function build_html(string $template = 'default', ?string $image = null, ?string $css = null, ?string $js = null): void
     {
-        $gen = new TemplateRenderer($template, $image);
+        $gen = new HtmlTemplateRenderer($template, $image);
 
         if (!is_null($css)) {
             $gen->css = explode(',', $css);
diff --git a/src/PHPDraft/Parse/ParserFactory.php b/src/PHPDraft/Parse/ParserFactory.php
index 20271564..4a45dda3 100644
--- a/src/PHPDraft/Parse/ParserFactory.php
+++ b/src/PHPDraft/Parse/ParserFactory.php
@@ -4,6 +4,8 @@
 
 namespace PHPDraft\Parse;
 
+use PHPDraft\Out\OpenAPI\OpenApiRenderer;
+
 /**
  * Class ParserFactory.
  */
@@ -39,4 +41,13 @@ public static function getJson(): BaseHtmlGenerator
 
         throw new ResourceException("Couldn't get a JSON parser", 255);
     }
+
+    public static function getOpenAPI(): OpenApiRenderer
+    {
+        if (Drafter::available() || DrafterAPI::available()) {
+            return new OpenApiRenderer();
+        }
+
+        throw new ResourceException("Couldn't get a JSON parser", 255);
+    }
 }