diff --git a/modules/apigee_edge_debug/apigee_edge_debug.services.yml b/modules/apigee_edge_debug/apigee_edge_debug.services.yml
index 51d6c631..0b054a5b 100644
--- a/modules/apigee_edge_debug/apigee_edge_debug.services.yml
+++ b/modules/apigee_edge_debug/apigee_edge_debug.services.yml
@@ -22,3 +22,9 @@ services:
     arguments: ['@config.factory', '@logger.channel.apigee_edge_debug', '@plugin.manager.apigee_edge_debug.debug_message_formatter']
     tags:
       - { name: http_client_middleware }
+
+  apigee_edge_debug.devel_client_profiler:
+    class: Drupal\apigee_edge_debug\HttpClientMiddleware\DevelKintApiClientProfiler
+    arguments: ['@config.factory', '@plugin.manager.apigee_edge_debug.debug_message_formatter', '@current_user', '@module_handler', '@messenger']
+    tags:
+      - { name: http_client_middleware }
diff --git a/modules/apigee_edge_debug/src/HttpClientMiddleware/DevelKintApiClientProfiler.php b/modules/apigee_edge_debug/src/HttpClientMiddleware/DevelKintApiClientProfiler.php
new file mode 100644
index 00000000..446311a7
--- /dev/null
+++ b/modules/apigee_edge_debug/src/HttpClientMiddleware/DevelKintApiClientProfiler.php
@@ -0,0 +1,153 @@
+<?php
+
+/**
+ * Copyright 2021 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+
+namespace Drupal\apigee_edge_debug\HttpClientMiddleware;
+
+use Drupal\apigee_edge_debug\DebugMessageFormatterPluginManager;
+use Drupal\apigee_edge_debug\SDKConnector;
+use Drupal\Core\Config\ConfigFactoryInterface;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Messenger\MessengerInterface;
+use GuzzleHttp\RequestOptions;
+use GuzzleHttp\TransferStats;
+use Psr\Http\Message\RequestInterface;
+use Psr\Log\LogLevel;
+
+/**
+ * Http client middleware that profiles Apigee Edge API calls.
+ */
+final class DevelKintApiClientProfiler {
+
+  /**
+   * The currently logged-in user.
+   *
+   * @var \Drupal\Core\Session\AccountInterface
+   */
+  private $currentUser;
+
+  /**
+   * The messenger service.
+   *
+   * @var \Drupal\Core\Messenger\MessengerInterface
+   */
+  private $messenger;
+
+  /**
+   * The debug message formatter plugin.
+   *
+   * @var \Drupal\apigee_edge_debug\Plugin\DebugMessageFormatter\DebugMessageFormatterPluginInterface
+   */
+  private $formatter;
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface|null
+   */
+  private $moduleHandler;
+
+  /**
+   * DevelKintApiClientProfiler constructor.
+   *
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
+   *   Config factory.
+   * @param \Drupal\apigee_edge_debug\DebugMessageFormatterPluginManager $debug_message_formatter_plugin
+   *   Debug message formatter plugin manager.
+   * @param \Drupal\Core\Session\AccountInterface $currentUser
+   *   The currently logged-in user.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler service.
+   * @param \Drupal\Core\Messenger\MessengerInterface $messenger
+   *   The messenger service.
+   */
+  public function __construct(ConfigFactoryInterface $config_factory, DebugMessageFormatterPluginManager $debug_message_formatter_plugin, AccountInterface $currentUser, ModuleHandlerInterface $module_handler, MessengerInterface $messenger) {
+    // On module install, this constructor is called earlier than
+    // the module's configuration would have been imported to the database.
+    // In that case the $formatterPluginId is missing and it causes fatal
+    // errors.
+    $formatter_plugin_id = $config_factory->get('apigee_edge_debug.settings')->get('formatter');
+    if ($formatter_plugin_id) {
+      $this->formatter = $debug_message_formatter_plugin->createInstance($formatter_plugin_id);
+    }
+    $this->currentUser = $currentUser;
+    $this->moduleHandler = $module_handler;
+    $this->messenger = $messenger;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __invoke() {
+    return function ($handler) {
+      return function (RequestInterface $request, array $options) use ($handler) {
+        // If devel kint module is enabled and the user has devel kint permission.
+        if ($this->moduleHandler->moduleExists('kint') && $this->currentUser->hasPermission('access kint')) {
+          // If the formatter has been initialized yet then do nothing.
+          if (!$this->formatter) {
+            return $handler($request, $options);
+          }
+          $formatter = $this->formatter;
+          $rest_call = [];
+          if (isset($options[RequestOptions::ON_STATS])) {
+            $next = $options[RequestOptions::ON_STATS];
+          }
+          else {
+            $next = function (TransferStats $stats) {};
+          }
+          $options[RequestOptions::ON_STATS] = function (TransferStats $stats) use ($request, $next, $formatter) {
+            $this->messenger->addStatus(t('<h3>Edge Calls</h3>'));
+            $level = LogLevel::DEBUG;
+            // Do not modify the original request object in the subsequent calls.
+            $request_clone = clone $request;
+            $rest_call['Request'] = $formatter->formatRequest($request_clone);
+            if ($stats->hasResponse()) {
+              // Do not modify the original response object in the subsequent calls.
+              $response_clone = clone $stats->getResponse();
+              $rest_call['Response'] = $formatter->formatResponse($response_clone, $request_clone);
+              if ($stats->getResponse()->getStatusCode() >= 400) {
+                $level = LogLevel::WARNING;
+              }
+            }
+            else {
+              $level = LogLevel::ERROR;
+              $error = $stats->getHandlerErrorData();
+              if (is_object($error)) {
+                if (method_exists($error, '__toString')) {
+                  $error = (string) $error;
+                }
+                else {
+                  $error = json_encode($error);
+                }
+              }
+              $rest_call['Error'] = $error;
+            }
+            $next($stats);
+            $rest_call['Time Elapsed'] = $formatter->formatStats($stats);
+            $rest_call['Severity'] = isset($level) ? $level : '';
+            ksm($rest_call);
+          };
+        }
+        return $handler($request, $options);
+      };
+    };
+  }
+
+}