diff --git a/readme.md b/readme.md
index 7741728..89ac7b7 100644
--- a/readme.md
+++ b/readme.md
@@ -1,4 +1,4 @@
-# PHP Library for the Nationanl Weather Service REST API
+# PHP Library for the National Weather Service REST API
 
 Provides an intuitive interface to use the NWS REST API in any PHP application.
 
diff --git a/src/Api.php b/src/Api.php
index ed4cf49..73686cc 100644
--- a/src/Api.php
+++ b/src/Api.php
@@ -14,7 +14,7 @@
 
 class Api
 {
-    protected Psr16Adapter|null $cache = null;
+    private Psr16Adapter|null $cache = null;
     private string $base_url = "https://api.weather.gov";
     private string $user_agent;
     private HttpClient $client;
@@ -43,10 +43,9 @@ public function getUserAgent(): string
         return $this->user_agent;
     }
 
-    public function setUserAgent(string $domain, string $email): self
+    private function setUserAgent(string $domain, string $email): void
     {
         $this->user_agent = "({$domain}, {$email})";
-        return $this;
     }
 
     public function getCacheLifetime(): int
diff --git a/src/Features/Point.php b/src/Features/Point.php
index 583b052..96fb34d 100644
--- a/src/Features/Point.php
+++ b/src/Features/Point.php
@@ -117,7 +117,7 @@ public function gridY(): int
         return $this->properties_gridY();
     }
 
-    public function latestObservations($observation_station_index = 0): LatestObservations
+    public function latestObservations(int $observation_station_index = 0): LatestObservations
     {
         return $this->observationStations()->station($observation_station_index)->latestObservations();
     }