diff --git a/src/Agent/AgentClient.php b/src/Agent/AgentClient.php
index 897424a..fe50972 100644
--- a/src/Agent/AgentClient.php
+++ b/src/Agent/AgentClient.php
@@ -17,6 +17,8 @@
 */
 
 use DCarbone\PHPConsulAPI\AbstractClient;
+use DCarbone\PHPConsulAPI\Consul;
+use DCarbone\PHPConsulAPI\Error;
 use DCarbone\PHPConsulAPI\Request;
 
 /**
@@ -199,7 +201,7 @@ public function serviceDeregister($serviceID) {
      * @return \DCarbone\PHPConsulAPI\Error|null
      */
     public function passTTL($checkID, $note) {
-        return $this->updateTTL($checkID, $note, 'passing');
+        return $this->updateTTL($checkID, $note, 'pass');
     }
 
     /**
@@ -210,7 +212,7 @@ public function passTTL($checkID, $note) {
      * @return \DCarbone\PHPConsulAPI\Error|null
      */
     public function warnTTL($checkID, $note) {
-        return $this->updateTTL($checkID, $note, 'warning');
+        return $this->updateTTL($checkID, $note, 'warn');
     }
 
     /**
@@ -221,7 +223,7 @@ public function warnTTL($checkID, $note) {
      * @return \DCarbone\PHPConsulAPI\Error|null
      */
     public function failTTL($checkID, $note) {
-        return $this->updateTTL($checkID, $note, 'critical');
+        return $this->updateTTL($checkID, $note, 'fail');
     }
 
     /**
@@ -233,6 +235,27 @@ public function failTTL($checkID, $note) {
      * @return \DCarbone\PHPConsulAPI\Error|null
      */
     public function updateTTL($checkID, $output, $status) {
+        switch ($status) {
+            case Consul::HealthPassing:
+            case Consul::HealthWarning:
+            case Consul::HealthCritical:
+                break;
+            case 'pass':
+                $status = Consul::HealthPassing;
+                break;
+            case 'warn':
+                $status = Consul::HealthWarning;
+                break;
+            case 'fail':
+                $status = Consul::HealthCritical;
+                break;
+            default:
+                return new Error(sprintf(
+                    '%s is not a valid status.  Allowed: ["pass", "warn", "fail"]',
+                    is_string($status) ? $status : gettype($status)
+                ));
+        }
+
         $r = new Request('put',
             sprintf('v1/agent/check/update/%s', $checkID),
             $this->c,
diff --git a/src/Agent/AgentServiceCheck.php b/src/Agent/AgentServiceCheck.php
index 7f3cdef..3728f76 100644
--- a/src/Agent/AgentServiceCheck.php
+++ b/src/Agent/AgentServiceCheck.php
@@ -41,6 +41,12 @@ class AgentServiceCheck extends AbstractModel {
     public $TCP = '';
     /** @var string */
     public $Status = '';
+    /** @var string */
+    public $Notes = '';
+    /** @var bool */
+    public $TLSSkipVerify = false;
+    /** @var string */
+    public $DeregisterCriticalServiceAfter = '';
 
     /**
      * @return string
@@ -185,4 +191,52 @@ public function setStatus($Status) {
         $this->Status = $Status;
         return $this;
     }
+
+    /**
+     * @return string
+     */
+    public function getNotes() {
+        return $this->Notes;
+    }
+
+    /**
+     * @param string $Notes
+     * @return \DCarbone\PHPConsulAPI\Agent\AgentServiceCheck
+     */
+    public function setNotes($Notes) {
+        $this->Notes = $Notes;
+        return $this;
+    }
+
+    /**
+     * @return bool
+     */
+    public function isTLSSkipVerify() {
+        return $this->TLSSkipVerify;
+    }
+
+    /**
+     * @param bool $TLSSkipVerify
+     * @return \DCarbone\PHPConsulAPI\Agent\AgentServiceCheck
+     */
+    public function setTLSSkipVerify($TLSSkipVerify) {
+        $this->TLSSkipVerify = $TLSSkipVerify;
+        return $this;
+    }
+
+    /**
+     * @return string
+     */
+    public function getDeregisterCriticalServiceAfter() {
+        return $this->DeregisterCriticalServiceAfter;
+    }
+
+    /**
+     * @param string $DeregisterCriticalServiceAfter
+     * @return \DCarbone\PHPConsulAPI\Agent\AgentServiceCheck
+     */
+    public function setDeregisterCriticalServiceAfter($DeregisterCriticalServiceAfter) {
+        $this->DeregisterCriticalServiceAfter = $DeregisterCriticalServiceAfter;
+        return $this;
+    }
 }
\ No newline at end of file
diff --git a/src/Consul.php b/src/Consul.php
index 324c730..8f52025 100644
--- a/src/Consul.php
+++ b/src/Consul.php
@@ -39,6 +39,12 @@ class Consul {
     const HTTPSSLEnvName = 'CONSUL_HTTP_SSL';
     const HTTPSSLVerifyEnvName = 'CONSUL_HTTP_SSL_VERIFY';
 
+    const HealthAny = 'any';
+    const HealthPassing = 'passing';
+    const HealthWarning = 'warning';
+    const HealthCritical = 'critical';
+    const HealthMaint = 'maintenance';
+
     /** @var \DCarbone\PHPConsulAPI\KV\KVClient */
     public $KV;
     /** @var \DCarbone\PHPConsulAPI\Agent\AgentClient */
diff --git a/src/Error.php b/src/Error.php
index e82873c..9db36a0 100644
--- a/src/Error.php
+++ b/src/Error.php
@@ -24,54 +24,48 @@
  */
 class Error implements \JsonSerializable {
     /** @var DateTime */
-    private $_timestamp;
+    private $time;
 
     /** @var string */
-    private $_message;
+    private $message;
 
     /**
      * Error constructor.
      * @param string $message
      */
     public function __construct($message) {
-        $this->_timestamp = new DateTime();
-        $this->_message = $message;
+        $this->time = new DateTime();
+        $this->message = $message;
     }
 
     /**
      * @return DateTime
      */
-    public function getTimestamp() {
-        return $this->_timestamp;
+    public function getTime() {
+        return $this->time;
     }
 
     /**
      * @return string
      */
     public function getMessage() {
-        return $this->_message;
+        return $this->message;
     }
 
     /**
-     * Specify data which should be serialized to JSON
-     * @link http://php.net/manual/en/jsonserializable.jsonserialize.php
-     * @return mixed data which can be serialized by json_encode, which is a value of any type other than a resource.
+     * @return array
      */
     public function jsonSerialize() {
-        return array(
-            'message' => $this->_message,
-            'timestamp' => $this->_timestamp
-        );
+        return [
+            'message' => $this->message,
+            'timestamp' => $this->time
+        ];
     }
 
     /**
      * @return string
      */
     public function __toString() {
-        return sprintf(
-            '[error] - %s - %s',
-            $this->_timestamp,
-            $this->_message
-        );
+        return $this->message;
     }
 }
\ No newline at end of file