diff --git a/src/main/java/net/knarcraft/dynmapcitizens/DynmapCitizens.java b/src/main/java/net/knarcraft/dynmapcitizens/DynmapCitizens.java
index 265f09d..fdf34e0 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/DynmapCitizens.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/DynmapCitizens.java
@@ -19,6 +19,7 @@ import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.PluginManager;
 import org.bukkit.plugin.java.JavaPlugin;
 import org.dynmap.DynmapAPI;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -112,7 +113,7 @@ public final class DynmapCitizens extends JavaPlugin {
      *
      * @return <p>The global settings for this plugin</p>
      */
-    public GlobalSettings getGlobalSettings() {
+    public @NotNull GlobalSettings getGlobalSettings() {
         return this.globalSettings;
     }
 
@@ -121,7 +122,7 @@ public final class DynmapCitizens extends JavaPlugin {
      *
      * @return <p>The Vault handler</p>
      */
-    public VaultHandler getVaultHandler() {
+    public @NotNull VaultHandler getVaultHandler() {
         return this.vaultHandler;
     }
 
@@ -130,7 +131,7 @@ public final class DynmapCitizens extends JavaPlugin {
      *
      * @return <p>A reference to the Dynmap API</p>
      */
-    public DynmapAPI getDynmapAPI() {
+    public @NotNull DynmapAPI getDynmapAPI() {
         return this.dynmapAPIInstance;
     }
 
@@ -148,7 +149,7 @@ public final class DynmapCitizens extends JavaPlugin {
      *
      * @param configuration <p>The configuration to read settings from</p>
      */
-    private void initializeTraitHandlers(FileConfiguration configuration) {
+    private void initializeTraitHandlers(@NotNull FileConfiguration configuration) {
         //Register all trait handlers
         this.traitHandlers = new ArrayList<>();
         this.traitHandlers.add(new BlacksmithHandler());
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/VaultHandler.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/VaultHandler.java
index d082ba4..756ec9e 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/VaultHandler.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/VaultHandler.java
@@ -3,6 +3,7 @@ package net.knarcraft.dynmapcitizens.handler;
 import net.milkbowl.vault.economy.Economy;
 import org.bukkit.plugin.RegisteredServiceProvider;
 import org.bukkit.plugin.ServicesManager;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * A class to keep track of everything Vault
@@ -16,7 +17,7 @@ public class VaultHandler {
      *
      * @param servicesManager <p>The services manager to get the Vault service from</p>
      */
-    public VaultHandler(ServicesManager servicesManager) {
+    public VaultHandler(@NotNull ServicesManager servicesManager) {
         RegisteredServiceProvider<Economy> economyProvider = servicesManager.getRegistration(Economy.class);
         if (economyProvider != null) {
             economy = economyProvider.getProvider();
@@ -37,7 +38,7 @@ public class VaultHandler {
      *
      * @return <p>The currency name</p>
      */
-    public String getCurrency(boolean plural) {
+    public @NotNull String getCurrency(boolean plural) {
         if (plural) {
             return economy.currencyNamePlural();
         } else {
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/AbstractTraitHandler.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/AbstractTraitHandler.java
index c869b65..154634c 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/AbstractTraitHandler.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/AbstractTraitHandler.java
@@ -12,6 +12,7 @@ import org.dynmap.DynmapAPI;
 import org.dynmap.markers.Marker;
 import org.dynmap.markers.MarkerIcon;
 import org.dynmap.markers.MarkerSet;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.UUID;
 
@@ -51,7 +52,8 @@ public abstract class AbstractTraitHandler implements CitizensTraitHandler {
      * @param icon              <p>The icon used for the marker</p>
      * @param markerSet         <p>The marker set to add the marker to</p>
      */
-    protected void addNPCMarker(UUID npcId, String markerName, String markerDescription, MarkerIcon icon, MarkerSet markerSet) {
+    protected void addNPCMarker(@NotNull UUID npcId, @NotNull String markerName, @NotNull String markerDescription,
+                                @NotNull MarkerIcon icon, @NotNull MarkerSet markerSet) {
         NPC npc = CitizensAPI.getNPCRegistry().getByUniqueId(npcId);
         //If the NPC has been removed, abort
         if (npc == null) {
@@ -89,7 +91,7 @@ public abstract class AbstractTraitHandler implements CitizensTraitHandler {
      * @param npc <p>The NPC to check</p>
      * @return <p>True if the NPC is currently moving about</p>
      */
-    protected boolean isMoving(NPC npc) {
+    protected boolean isMoving(@NotNull NPC npc) {
         return npc.getNavigator().getTargetAsLocation() != null;
     }
 
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/BlacksmithHandler.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/BlacksmithHandler.java
index 601d559..eb06ea9 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/BlacksmithHandler.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/BlacksmithHandler.java
@@ -13,6 +13,7 @@ import net.knarcraft.dynmapcitizens.settings.TraitSettings;
 import org.bukkit.Bukkit;
 import org.bukkit.Material;
 import org.dynmap.markers.GenericMarker;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -27,7 +28,8 @@ public class BlacksmithHandler extends AbstractTraitHandler {
 
     @Override
     public void initialize() {
-        BlacksmithPlugin blacksmithPlugin = (BlacksmithPlugin) Bukkit.getServer().getPluginManager().getPlugin("Blacksmith");
+        BlacksmithPlugin blacksmithPlugin = (BlacksmithPlugin) Bukkit.getServer().getPluginManager().getPlugin(
+                "Blacksmith");
         if (blacksmithPlugin != null) {
             super.initializeMarkerSet();
         } else {
@@ -36,7 +38,7 @@ public class BlacksmithHandler extends AbstractTraitHandler {
     }
 
     @Override
-    public TraitSettings getSettings() {
+    public @NotNull TraitSettings getSettings() {
         return this.settings;
     }
 
@@ -49,7 +51,7 @@ public class BlacksmithHandler extends AbstractTraitHandler {
         for (NPC npc : CitizensAPI.getNPCRegistry()) {
             if (npc.hasTrait(blacksmithTrait)) {
                 BlacksmithTrait trait = npc.getTraitNullable(BlacksmithTrait.class);
-                String description = null;
+                String description = "";
                 if (trait == null) {
                     DynmapCitizens.getInstance().getLogger().log(Level.WARNING, "Unable to get blacksmith trait");
                 } else {
@@ -69,7 +71,7 @@ public class BlacksmithHandler extends AbstractTraitHandler {
      * @param npcSettings <p>The settings to search for information</p>
      * @return <p>A string describing the blacksmith</p>
      */
-    private String getDetailedBlacksmithInfo(NPC npc, NPCSettings npcSettings) {
+    private @NotNull String getDetailedBlacksmithInfo(@NotNull NPC npc, @NotNull NPCSettings npcSettings) {
         String info = "<h2>" + npc.getName() + " the " +
                 npcSettings.getBlacksmithTitle() + "</h2>";
         if (settings.displayBlacksmithSettings()) {
@@ -91,7 +93,7 @@ public class BlacksmithHandler extends AbstractTraitHandler {
      * @param materials <p>The materials specified as reforge-able items</p>
      * @return <p>The reforge-able items</p>
      */
-    private static String getReforgeAbleItemsString(List<Material> materials) {
+    private static @NotNull String getReforgeAbleItemsString(@NotNull List<Material> materials) {
         List<String> materialNames = new ArrayList<>();
         for (Material material : materials) {
             materialNames.add(material.name());
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/CitizensTraitHandler.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/CitizensTraitHandler.java
index c740edf..1cc8a42 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/CitizensTraitHandler.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/CitizensTraitHandler.java
@@ -1,6 +1,7 @@
 package net.knarcraft.dynmapcitizens.handler.trait;
 
 import net.knarcraft.dynmapcitizens.settings.TraitSettings;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * A handler which takes care of everything for one citizen trait
@@ -24,7 +25,7 @@ public interface CitizensTraitHandler {
      *
      * @return <p>The settings for this trait</p>
      */
-    TraitSettings getSettings();
+    @NotNull TraitSettings getSettings();
 
     /**
      * Updates all markers used for this handler
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/DTLTradersHandler.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/DTLTradersHandler.java
index 9657fda..635e114 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/DTLTradersHandler.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/DTLTradersHandler.java
@@ -8,6 +8,7 @@ import net.knarcraft.dynmapcitizens.property.Icon;
 import net.knarcraft.dynmapcitizens.settings.DTLTradersSettings;
 import net.knarcraft.dynmapcitizens.settings.TraitSettings;
 import org.dynmap.markers.GenericMarker;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * A handler class for the minstrel trait
@@ -31,7 +32,7 @@ public class DTLTradersHandler extends AbstractTraitHandler {
     }
 
     @Override
-    public TraitSettings getSettings() {
+    public @NotNull TraitSettings getSettings() {
         return this.settings;
     }
 
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/MinstrelHandler.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/MinstrelHandler.java
index d4b8708..fb0b15b 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/MinstrelHandler.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/MinstrelHandler.java
@@ -12,6 +12,7 @@ import net.knarcraft.minstrel.music.Song;
 import net.knarcraft.minstrel.trait.MinstrelTrait;
 import org.bukkit.Bukkit;
 import org.dynmap.markers.GenericMarker;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.logging.Level;
 
@@ -33,7 +34,7 @@ public class MinstrelHandler extends AbstractTraitHandler {
     }
 
     @Override
-    public TraitSettings getSettings() {
+    public @NotNull TraitSettings getSettings() {
         return this.settings;
     }
 
@@ -46,7 +47,7 @@ public class MinstrelHandler extends AbstractTraitHandler {
         for (NPC npc : CitizensAPI.getNPCRegistry()) {
             if (npc.hasTrait(minstrelTrait)) {
                 MinstrelTrait trait = npc.getTraitNullable(MinstrelTrait.class);
-                String description = null;
+                String description = "";
                 if (trait == null) {
                     DynmapCitizens.getInstance().getLogger().log(Level.WARNING, "Unable to get minstrel trait");
                 } else {
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/SentinelHandler.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/SentinelHandler.java
index dc0938e..7b72946 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/SentinelHandler.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/SentinelHandler.java
@@ -9,6 +9,7 @@ import net.knarcraft.dynmapcitizens.settings.SentinelSettings;
 import net.knarcraft.dynmapcitizens.settings.TraitSettings;
 import org.bukkit.Bukkit;
 import org.dynmap.markers.GenericMarker;
+import org.jetbrains.annotations.NotNull;
 import org.mcmonkey.sentinel.SentinelPlugin;
 import org.mcmonkey.sentinel.SentinelTrait;
 
@@ -30,7 +31,7 @@ public class SentinelHandler extends AbstractTraitHandler {
     }
 
     @Override
-    public TraitSettings getSettings() {
+    public @NotNull TraitSettings getSettings() {
         return this.settings;
     }
 
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/NPCQuestInfo.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/NPCQuestInfo.java
index 7082751..6802cd5 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/NPCQuestInfo.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/NPCQuestInfo.java
@@ -2,6 +2,7 @@ package net.knarcraft.dynmapcitizens.handler.trait.quests;
 
 import me.blackvein.quests.quests.IQuest;
 import net.knarcraft.dynmapcitizens.property.Icon;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -21,7 +22,7 @@ public class NPCQuestInfo {
      *
      * @param quest <p>The quest to add</p>
      */
-    public void addQuestStart(IQuest quest) {
+    public void addQuestStart(@NotNull IQuest quest) {
         this.questStart.add(quest);
     }
 
@@ -30,7 +31,7 @@ public class NPCQuestInfo {
      *
      * @param quest <p>The quest to add</p>
      */
-    public void addQuestKill(IQuest quest) {
+    public void addQuestKill(@NotNull IQuest quest) {
         this.questKill.add(quest);
     }
 
@@ -39,7 +40,7 @@ public class NPCQuestInfo {
      *
      * @param quest <p>The quest to add</p>
      */
-    public void addQuestDeliver(IQuest quest) {
+    public void addQuestDeliver(@NotNull IQuest quest) {
         this.questDeliver.add(quest);
     }
 
@@ -48,7 +49,7 @@ public class NPCQuestInfo {
      *
      * @param quest <p>The quest to add</p>
      */
-    public void addQuestInteract(IQuest quest) {
+    public void addQuestInteract(@NotNull IQuest quest) {
         this.questInteract.add(quest);
     }
 
@@ -57,7 +58,7 @@ public class NPCQuestInfo {
      *
      * @return <p>All quests this NPC is used to start</p>
      */
-    public List<IQuest> getQuestStarts() {
+    public @NotNull List<IQuest> getQuestStarts() {
         return new ArrayList<>(this.questStart);
     }
 
@@ -66,7 +67,7 @@ public class NPCQuestInfo {
      *
      * @return <p>All kill quests involving this NPC</p>
      */
-    public List<IQuest> getQuestKills() {
+    public @NotNull List<IQuest> getQuestKills() {
         return new ArrayList<>(this.questKill);
     }
 
@@ -75,7 +76,7 @@ public class NPCQuestInfo {
      *
      * @return <p>All quests delivering to this NPC</p>
      */
-    public List<IQuest> getQuestDeliveries() {
+    public @NotNull List<IQuest> getQuestDeliveries() {
         return new ArrayList<>(this.questDeliver);
     }
 
@@ -84,7 +85,7 @@ public class NPCQuestInfo {
      *
      * @return <p>All quests requiring interaction with this NPC</p>
      */
-    public List<IQuest> getQuestInteractions() {
+    public @NotNull List<IQuest> getQuestInteractions() {
         return new ArrayList<>(this.questInteract);
     }
 
@@ -93,7 +94,7 @@ public class NPCQuestInfo {
      *
      * @return <p>The main type of the quest NPC</p>
      */
-    public QuestNPCType getQuestNPCType() {
+    public @NotNull QuestNPCType getQuestNPCType() {
         if (!questStart.isEmpty()) {
             return QuestNPCType.GIVER;
         } else if (!questKill.isEmpty() && questInteract.isEmpty() && questDeliver.isEmpty()) {
@@ -112,7 +113,7 @@ public class NPCQuestInfo {
      *
      * @return <p>The icon used to mark this NPC</p>
      */
-    public Icon getNPCIcon() {
+    public @NotNull Icon getNPCIcon() {
         QuestNPCType type = getQuestNPCType();
         return switch (type) {
             case KILL -> Icon.QUEST_KILL;
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestAreaHandler.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestAreaHandler.java
index adf80b8..8089b65 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestAreaHandler.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestAreaHandler.java
@@ -15,6 +15,7 @@ import org.bukkit.entity.EntityType;
 import org.dynmap.DynmapAPI;
 import org.dynmap.markers.GenericMarker;
 import org.dynmap.markers.MarkerSet;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
 
@@ -43,8 +44,8 @@ public class QuestAreaHandler {
      * @param settings          <p>The quests settings to use</p>
      * @param unavailableQuests <p>The list of currently unavailable quests to possibly skip</p>
      */
-    public QuestAreaHandler(QuestsAPI questsAPI, DynmapAPI dynmapAPI, QuestsSettings settings,
-                            List<IQuest> unavailableQuests) {
+    public QuestAreaHandler(@NotNull QuestsAPI questsAPI, @NotNull DynmapAPI dynmapAPI, @NotNull QuestsSettings settings,
+                            @NotNull List<IQuest> unavailableQuests) {
         this.questsAPI = questsAPI;
         this.settings = settings;
         this.unavailableQuests = unavailableQuests;
@@ -78,7 +79,7 @@ public class QuestAreaHandler {
      * @param quest <p>The quest the stage belongs to</p>
      * @param stage <p>The stage to search for reach locations</p>
      */
-    private void markReachLocations(IQuest quest, IStage stage) {
+    private void markReachLocations(@NotNull IQuest quest, @NotNull IStage stage) {
         if (settings.getReachAreaSettings().isDisabled()) {
             return;
         }
@@ -106,7 +107,7 @@ public class QuestAreaHandler {
      * @param quest <p>The quest the stage belongs to</p>
      * @param stage <p>The stage to search for kill locations</p>
      */
-    private void markKillLocations(IQuest quest, IStage stage) {
+    private void markKillLocations(@NotNull IQuest quest, @NotNull IStage stage) {
         if (settings.getKillAreaSettings().isDisabled()) {
             return;
         }
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestNPCType.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestNPCType.java
index ea90965..c7d1af4 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestNPCType.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestNPCType.java
@@ -1,5 +1,7 @@
 package net.knarcraft.dynmapcitizens.handler.trait.quests;
 
+import org.jetbrains.annotations.NotNull;
+
 /**
  * A specifier for a quest NPC's main type
  */
@@ -8,26 +10,47 @@ public enum QuestNPCType {
     /**
      * An NPC responsible for giving quests
      */
-    GIVER,
+    GIVER("Quest Start NPC: "),
 
     /**
      * An NPC killed in a quest
      */
-    KILL,
+    KILL("Quest Kill NPC: "),
 
     /**
      * An NPC set as the delivery target in a quest
      */
-    DELIVER,
+    DELIVER("Quest Deliver NPC: "),
 
     /**
      * An NPC to be interacted with in a quest
      */
-    INTERACT,
+    INTERACT("Quest Interact NPC: "),
 
     /**
      * An NPC which is not a quest giver, but has several tasks as part of other quests
      */
-    CHAIN
+    CHAIN("Quest Chain NPC: "),
+    ;
+
+    private final String markerTitle;
+
+    /**
+     * Instantiates a new Quest NPC type
+     *
+     * @param markerTitle <p>The title of the marker for this type of quest NPC</p>
+     */
+    QuestNPCType(@NotNull String markerTitle) {
+        this.markerTitle = markerTitle;
+    }
+
+    /**
+     * Gets the marker title for this Quest NPC type
+     *
+     * @return <p>The marker title</p>
+     */
+    public String getMarkerTitle() {
+        return this.markerTitle;
+    }
 
 }
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestPlannerInfoGenerator.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestPlannerInfoGenerator.java
index d3bce69..e266d68 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestPlannerInfoGenerator.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestPlannerInfoGenerator.java
@@ -4,6 +4,7 @@ import me.blackvein.quests.quests.IQuest;
 import me.blackvein.quests.quests.Planner;
 import net.knarcraft.dynmapcitizens.DynmapCitizens;
 import net.knarcraft.knarlib.formatting.TimeFormatter;
+import org.jetbrains.annotations.NotNull;
 
 import java.text.DateFormat;
 import java.text.SimpleDateFormat;
@@ -21,7 +22,7 @@ public class QuestPlannerInfoGenerator {
      *
      * @param quest <p>The quest to generate information about</p>
      */
-    public QuestPlannerInfoGenerator(IQuest quest) {
+    public QuestPlannerInfoGenerator(@NotNull IQuest quest) {
         this.quest = quest;
     }
 
@@ -30,7 +31,7 @@ public class QuestPlannerInfoGenerator {
      *
      * @return <p>Information about when the quest is available</p>
      */
-    public String getQuestPlannerInfo() {
+    public @NotNull String getQuestPlannerInfo() {
         Planner planner = quest.getPlanner();
         StringBuilder plannerInfo = new StringBuilder();
         plannerInfo.append("<b>Planner:</b><ul>");
@@ -74,7 +75,7 @@ public class QuestPlannerInfoGenerator {
      * @param timestamp <p>A timestamp in milliseconds</p>
      * @return <p>A datetime string</p>
      */
-    private String formatTimestamp(long timestamp) {
+    private @NotNull String formatTimestamp(long timestamp) {
         DateFormat format = new SimpleDateFormat("dd MM yyyy HH:mm:ss");
         Date date = new Date(timestamp);
         return format.format(date);
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestRequirementsInfoGenerator.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestRequirementsInfoGenerator.java
index 03f2dc0..c12472a 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestRequirementsInfoGenerator.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestRequirementsInfoGenerator.java
@@ -9,6 +9,8 @@ import net.knarcraft.knarlib.formatting.StringFormatter;
 import net.knarcraft.knarlib.formatting.StringReplacer;
 import net.knarcraft.knarlib.formatting.TranslatableMessage;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -42,7 +44,7 @@ public class QuestRequirementsInfoGenerator {
      * @param questsAPI <p>The API to use for getting quest information</p>
      * @param quest     <p>The quest to generate information about</p>
      */
-    public QuestRequirementsInfoGenerator(QuestsAPI questsAPI, IQuest quest) {
+    public QuestRequirementsInfoGenerator(@NotNull QuestsAPI questsAPI, @NotNull IQuest quest) {
         this.questsAPI = questsAPI;
         this.quest = quest;
         formatter = DynmapCitizens.getFormatter();
@@ -53,7 +55,7 @@ public class QuestRequirementsInfoGenerator {
      *
      * @return <p>Information about the quest's requirements</p>
      */
-    public String getQuestRequirementsInfo() {
+    public @NotNull String getQuestRequirementsInfo() {
         Requirements requirements = quest.getRequirements();
         if (!requirements.hasRequirement()) {
             return "";
@@ -131,7 +133,7 @@ public class QuestRequirementsInfoGenerator {
      * @param items <p>The items to get the names of</p>
      * @return <p>The names of the given items</p>
      */
-    private List<String> getItemNames(List<ItemStack> items) {
+    private @NotNull List<String> getItemNames(@NotNull List<ItemStack> items) {
         List<String> itemNames = new ArrayList<>();
         for (ItemStack itemStack : items) {
             itemNames.add(QuestsHelper.getUpperCasedItemStackString(itemStack));
@@ -145,7 +147,7 @@ public class QuestRequirementsInfoGenerator {
      * @param questIds <p>The quests to get names for</p>
      * @return <p>A list of quest names</p>
      */
-    private List<String> getQuestNames(List<String> questIds) {
+    private @NotNull List<String> getQuestNames(@NotNull List<String> questIds) {
         List<String> questNames = new ArrayList<>(questIds.size());
         for (String questId : questIds) {
             IQuest quest = getQuest(questId);
@@ -162,7 +164,7 @@ public class QuestRequirementsInfoGenerator {
      * @param questId <p>The id of the quest to get</p>
      * @return <p>The quest, or null if not found</p>
      */
-    private IQuest getQuest(String questId) {
+    private @Nullable IQuest getQuest(@NotNull String questId) {
         for (IQuest quest : questsAPI.getLoadedQuests()) {
             if (quest.getId().equals(questId)) {
                 return quest;
@@ -181,8 +183,9 @@ public class QuestRequirementsInfoGenerator {
      * @param itemPlaceholder   <p>The placeholder to replace with each item in the list</p>
      * @return <p>The string corresponding to the given requirement list</p>
      */
-    private String getRequirementList(List<String> itemList, TranslatableMessage formatMessage, String formatPlaceholder,
-                                      TranslatableMessage itemMessage, String itemPlaceholder) {
+    private @NotNull String getRequirementList(@NotNull List<String> itemList, @NotNull TranslatableMessage formatMessage,
+                                               @NotNull String formatPlaceholder, @NotNull TranslatableMessage itemMessage,
+                                               @NotNull String itemPlaceholder) {
         StringBuilder blockedBuilder = new StringBuilder();
         for (Object requirements : itemList) {
             blockedBuilder.append(formatter.replacePlaceholder(itemMessage, itemPlaceholder,
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestRewardsInfoGenerator.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestRewardsInfoGenerator.java
index be055e7..0f2aa64 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestRewardsInfoGenerator.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestRewardsInfoGenerator.java
@@ -4,6 +4,7 @@ import me.blackvein.quests.quests.IQuest;
 import me.blackvein.quests.quests.Rewards;
 import net.knarcraft.dynmapcitizens.util.QuestsHelper;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * A class to generate a string containing all information about a quest's rewards
@@ -17,7 +18,7 @@ public class QuestRewardsInfoGenerator {
      *
      * @param quest <p>The quest to generate information about</p>
      */
-    public QuestRewardsInfoGenerator(IQuest quest) {
+    public QuestRewardsInfoGenerator(@NotNull IQuest quest) {
         this.quest = quest;
     }
 
@@ -26,13 +27,14 @@ public class QuestRewardsInfoGenerator {
      *
      * @return <p>Information about the quest's rewards</p>
      */
-    public String getQuestRewardsInfo() {
+    public @NotNull String getQuestRewardsInfo() {
         Rewards reward = quest.getRewards();
         StringBuilder rewardInfo = new StringBuilder();
         rewardInfo.append("<b>Rewards:</b><ul>");
 
         if (reward.getMoney() > 0) {
-            rewardInfo.append("<li>").append(reward.getMoney()).append(" ").append(QuestsHelper.getCurrency(reward.getMoney())).append("</li>");
+            rewardInfo.append("<li>").append(reward.getMoney()).append(" ").append(QuestsHelper.getCurrency(
+                    reward.getMoney())).append("</li>");
         }
 
         if (reward.getExp() > 0) {
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestStagesInfoGenerator.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestStagesInfoGenerator.java
index f91575d..bba3998 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestStagesInfoGenerator.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestStagesInfoGenerator.java
@@ -8,6 +8,7 @@ import net.citizensnpcs.api.npc.NPCRegistry;
 import net.knarcraft.dynmapcitizens.util.QuestsHelper;
 import org.bukkit.Location;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
 import java.util.UUID;
@@ -24,7 +25,7 @@ public class QuestStagesInfoGenerator {
      *
      * @param quest <p>The quest to generate information about</p>
      */
-    public QuestStagesInfoGenerator(IQuest quest) {
+    public QuestStagesInfoGenerator(@NotNull IQuest quest) {
         this.quest = quest;
     }
 
@@ -33,7 +34,7 @@ public class QuestStagesInfoGenerator {
      *
      * @return <p>A string with information about the quest's stages</p>
      */
-    public String getQuestStagesInfo() {
+    public @NotNull String getQuestStagesInfo() {
         StringBuilder questInfo = new StringBuilder();
         NPCRegistry registry = CitizensAPI.getNPCRegistry();
         int stageCounter = 1;
@@ -64,7 +65,7 @@ public class QuestStagesInfoGenerator {
      * @param registry <p>The registry to get NPC info from</p>
      * @return <p>Information about the stage's tasks</p>
      */
-    private String getStageInfo(IStage stage, NPCRegistry registry) {
+    private @NotNull String getStageInfo(@NotNull IStage stage, @NotNull NPCRegistry registry) {
         StringBuilder questInfo = new StringBuilder();
         int mobTypes = stage.getMobsToKill().size();
         for (int i = 0; i < mobTypes; i++) {
@@ -134,7 +135,7 @@ public class QuestStagesInfoGenerator {
      * @param location <p>The location to show</p>
      * @return <p>A human-friendly location string</p>
      */
-    private String getLocationString(Location location) {
+    private @NotNull String getLocationString(@NotNull Location location) {
         String locationString = location.getX() + "," + location.getY() + "," + location.getZ();
         if (location.getWorld() != null) {
             locationString += " in world \"" + location.getWorld().getName() + "\"";
@@ -149,7 +150,7 @@ public class QuestStagesInfoGenerator {
      * @param explanation <p>The explanation of what the player needs to do with the items</p>
      * @return <p>A string describing the necessary tasks</p>
      */
-    private String getQuestItemsTaskString(List<ItemStack> items, String explanation) {
+    private @NotNull String getQuestItemsTaskString(@NotNull List<ItemStack> items, @NotNull String explanation) {
         StringBuilder questInfo = new StringBuilder();
         for (ItemStack itemStack : items) {
             questInfo.append(explanation).append(QuestsHelper.getItemStackString(itemStack));
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestsHandler.java b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestsHandler.java
index b68cf7c..58edd61 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestsHandler.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/handler/trait/quests/QuestsHandler.java
@@ -16,6 +16,7 @@ import org.dynmap.DynmapAPI;
 import org.dynmap.markers.GenericMarker;
 import org.dynmap.markers.Marker;
 import org.dynmap.markers.MarkerIcon;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -52,7 +53,7 @@ public class QuestsHandler extends AbstractTraitHandler {
     }
 
     @Override
-    public TraitSettings getSettings() {
+    public @NotNull TraitSettings getSettings() {
         return this.settings;
     }
 
@@ -140,7 +141,7 @@ public class QuestsHandler extends AbstractTraitHandler {
                     existingMarker.setDescription(newDescription);
                 }
             } else {
-                addNPCMarker(npcId, QuestsHelper.getMarkerTitle(info.getQuestNPCType()), newDescription, icon, super.markerSet);
+                addNPCMarker(npcId, info.getQuestNPCType().getMarkerTitle(), newDescription, icon, super.markerSet);
             }
         }
     }
@@ -151,7 +152,7 @@ public class QuestsHandler extends AbstractTraitHandler {
      * @param stringBuilder <p>The string builder to append to</p>
      * @param offeredQuests <p>The list of quests the NPC offers</p>
      */
-    private void appendOfferedQuestsInfo(StringBuilder stringBuilder, List<IQuest> offeredQuests) {
+    private void appendOfferedQuestsInfo(@NotNull StringBuilder stringBuilder, @NotNull List<IQuest> offeredQuests) {
         stringBuilder.append("<h3>Quests offered:</h3><ul>");
         for (IQuest quest : offeredQuests) {
             stringBuilder.append("<li><h4><b>").append(quest.getName()).append("</b></h4><h5><b>- ");
@@ -179,7 +180,7 @@ public class QuestsHandler extends AbstractTraitHandler {
      * @param info <p>The NPC info to look through</p>
      * @return <p>Information about an NPC's involvement in different quests</p>
      */
-    private String getInvolvedInQuestsString(NPCQuestInfo info) {
+    private String getInvolvedInQuestsString(@NotNull NPCQuestInfo info) {
         List<IQuest> questKills = info.getQuestKills();
         List<IQuest> questInteractions = info.getQuestInteractions();
         List<IQuest> questDeliveries = info.getQuestDeliveries();
@@ -203,7 +204,8 @@ public class QuestsHandler extends AbstractTraitHandler {
      * @param quests  <p>The quests the NPC is involved in</p>
      * @param builder <p>The string builder to append to</p>
      */
-    private void addInvolvedInString(String prefix, List<IQuest> quests, StringBuilder builder) {
+    private void addInvolvedInString(@NotNull String prefix, @NotNull List<IQuest> quests,
+                                     @NotNull StringBuilder builder) {
         for (IQuest quest : new HashSet<>(quests)) {
             builder.append("<li>").append(prefix).append(": ").append(quest.getName()).append("</li>");
         }
@@ -216,7 +218,7 @@ public class QuestsHandler extends AbstractTraitHandler {
      * @param npcId <p>The id of the NPC to get information about</p>
      * @return <p>The NPC's info object</p>
      */
-    private NPCQuestInfo getInfo(UUID npcId) {
+    private @NotNull NPCQuestInfo getInfo(@NotNull UUID npcId) {
         if (questGiverInfo.get(npcId) == null) {
             questGiverInfo.put(npcId, new NPCQuestInfo());
         }
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/settings/AbstractTraitSettings.java b/src/main/java/net/knarcraft/dynmapcitizens/settings/AbstractTraitSettings.java
index e767e10..810d7e4 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/settings/AbstractTraitSettings.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/settings/AbstractTraitSettings.java
@@ -1,6 +1,7 @@
 package net.knarcraft.dynmapcitizens.settings;
 
 import org.bukkit.configuration.file.FileConfiguration;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * An abstract implementation of trait settings
@@ -14,7 +15,7 @@ public abstract class AbstractTraitSettings implements TraitSettings {
     private String markerSetName;
 
     @Override
-    public void load(FileConfiguration configuration) {
+    public void load(@NotNull FileConfiguration configuration) {
         this.isEnabled = configuration.getBoolean(getTraitConfigRoot() + ".enabled", false);
         this.markerSetId = configuration.getString(getTraitConfigRoot() + ".markerSetId", null);
         this.markerSetPriority = configuration.getInt(getTraitConfigRoot() + ".markerSetPriority", 1);
@@ -28,12 +29,12 @@ public abstract class AbstractTraitSettings implements TraitSettings {
     }
 
     @Override
-    public String getMarkerSetId() {
+    public @NotNull String getMarkerSetId() {
         return markerSetId;
     }
 
     @Override
-    public String getMarkerSetName() {
+    public @NotNull String getMarkerSetName() {
         return markerSetName;
     }
 
@@ -52,6 +53,6 @@ public abstract class AbstractTraitSettings implements TraitSettings {
      *
      * @return <p>The root config node for this trait's settings</p>
      */
-    protected abstract String getTraitConfigRoot();
+    protected abstract @NotNull String getTraitConfigRoot();
 
 }
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/settings/AreaMarkerSettings.java b/src/main/java/net/knarcraft/dynmapcitizens/settings/AreaMarkerSettings.java
index f581383..febb29d 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/settings/AreaMarkerSettings.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/settings/AreaMarkerSettings.java
@@ -1,6 +1,7 @@
 package net.knarcraft.dynmapcitizens.settings;
 
 import org.bukkit.configuration.file.FileConfiguration;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Stores information about one kind of area marker
@@ -24,7 +25,7 @@ public class AreaMarkerSettings {
      * @param fileConfiguration <p>The file configuration to load settings from</p>
      * @param configRoot        <p>The config root node containing all config values for one marker</p>
      */
-    public void load(FileConfiguration fileConfiguration, String configRoot) {
+    public void load(@NotNull FileConfiguration fileConfiguration, @NotNull String configRoot) {
         this.enabled = fileConfiguration.getBoolean(configRoot + ".enabled", false);
         this.markerSetPriority = fileConfiguration.getInt(configRoot + ".markerSetPriority", 1);
         this.markerSetId = fileConfiguration.getString(configRoot + ".markerSetId", null);
@@ -60,7 +61,7 @@ public class AreaMarkerSettings {
      *
      * @return <p>The dynmap id of this marker set</p>
      */
-    public String getMarkerSetId() {
+    public @NotNull String getMarkerSetId() {
         return this.markerSetId;
     }
 
@@ -69,7 +70,7 @@ public class AreaMarkerSettings {
      *
      * @return <p>The name of this marker set</p>
      */
-    public String getMarkerSetName() {
+    public @NotNull String getMarkerSetName() {
         return this.markerSetName;
     }
 
@@ -87,7 +88,7 @@ public class AreaMarkerSettings {
      *
      * @return <p>The marker fill color</p>
      */
-    public String getFillColor() {
+    public @NotNull String getFillColor() {
         return this.fillColor;
     }
 
@@ -96,7 +97,7 @@ public class AreaMarkerSettings {
      *
      * @return <p>The marker outline color</p>
      */
-    public String getLineColor() {
+    public @NotNull String getLineColor() {
         return this.lineColor;
     }
 
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/settings/BlacksmithSettings.java b/src/main/java/net/knarcraft/dynmapcitizens/settings/BlacksmithSettings.java
index 533c21d..e9de87f 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/settings/BlacksmithSettings.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/settings/BlacksmithSettings.java
@@ -1,6 +1,7 @@
 package net.knarcraft.dynmapcitizens.settings;
 
 import org.bukkit.configuration.file.FileConfiguration;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * All settings for the blacksmith trait
@@ -10,13 +11,13 @@ public class BlacksmithSettings extends AbstractTraitSettings {
     private boolean displayBlacksmithSettings;
 
     @Override
-    public void load(FileConfiguration configuration) {
+    public void load(@NotNull FileConfiguration configuration) {
         super.load(configuration);
         displayBlacksmithSettings = configuration.getBoolean(getTraitConfigRoot() + ".displayBlacksmithSettings", true);
     }
 
     @Override
-    protected String getTraitConfigRoot() {
+    protected @NotNull String getTraitConfigRoot() {
         return "traits.blacksmith";
     }
 
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/settings/DTLTradersSettings.java b/src/main/java/net/knarcraft/dynmapcitizens/settings/DTLTradersSettings.java
index 80b3593..c107502 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/settings/DTLTradersSettings.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/settings/DTLTradersSettings.java
@@ -1,6 +1,7 @@
 package net.knarcraft.dynmapcitizens.settings;
 
 import org.bukkit.configuration.file.FileConfiguration;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * All settings for the minstrel trait
@@ -8,12 +9,12 @@ import org.bukkit.configuration.file.FileConfiguration;
 public class DTLTradersSettings extends AbstractTraitSettings {
 
     @Override
-    public void load(FileConfiguration configuration) {
+    public void load(@NotNull FileConfiguration configuration) {
         super.load(configuration);
     }
 
     @Override
-    protected String getTraitConfigRoot() {
+    protected @NotNull String getTraitConfigRoot() {
         return "traits.trader";
     }
 
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/settings/GlobalSettings.java b/src/main/java/net/knarcraft/dynmapcitizens/settings/GlobalSettings.java
index 47f70bd..04f66a5 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/settings/GlobalSettings.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/settings/GlobalSettings.java
@@ -6,6 +6,7 @@ import org.bukkit.configuration.file.FileConfiguration;
 import org.dynmap.DynmapAPI;
 import org.dynmap.markers.MarkerAPI;
 import org.dynmap.markers.MarkerIcon;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -24,7 +25,7 @@ public class GlobalSettings {
      *
      * @param configuration <p>The configuration to load from</p>
      */
-    public void load(FileConfiguration configuration) {
+    public void load(@NotNull FileConfiguration configuration) {
         DynmapAPI dynmapAPI = DynmapCitizens.getInstance().getDynmapAPI();
         MarkerAPI markerAPI = dynmapAPI.getMarkerAPI();
 
@@ -43,7 +44,7 @@ public class GlobalSettings {
      *
      * @return <p>The marker icons to use</p>
      */
-    public Map<Icon, MarkerIcon> getMarkerIcons() {
+    public @NotNull Map<Icon, MarkerIcon> getMarkerIcons() {
         return new HashMap<>(markerIcons);
     }
 
@@ -71,7 +72,7 @@ public class GlobalSettings {
      * @param icon <p>The icon identifier to get the icon for</p>
      * @return <p>The default icon name</p>
      */
-    private String getDefaultIconName(Icon icon) {
+    private @NotNull String getDefaultIconName(@NotNull Icon icon) {
         //The advantage of this switch over a map is that it will throw an error if a case is missing
         return switch (icon) {
             case QUEST_GIVER -> "exclamation";
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/settings/MinstrelSettings.java b/src/main/java/net/knarcraft/dynmapcitizens/settings/MinstrelSettings.java
index bf63599..3ebc246 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/settings/MinstrelSettings.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/settings/MinstrelSettings.java
@@ -1,6 +1,7 @@
 package net.knarcraft.dynmapcitizens.settings;
 
 import org.bukkit.configuration.file.FileConfiguration;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * All settings for the minstrel trait
@@ -10,13 +11,13 @@ public class MinstrelSettings extends AbstractTraitSettings {
     private boolean displayMinstrelSongs;
 
     @Override
-    public void load(FileConfiguration configuration) {
+    public void load(@NotNull FileConfiguration configuration) {
         super.load(configuration);
         displayMinstrelSongs = configuration.getBoolean(getTraitConfigRoot() + ".displayMinstrelSongs", true);
     }
 
     @Override
-    protected String getTraitConfigRoot() {
+    protected @NotNull String getTraitConfigRoot() {
         return "traits.minstrel";
     }
 
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/settings/QuestsSettings.java b/src/main/java/net/knarcraft/dynmapcitizens/settings/QuestsSettings.java
index 385c695..3d6abe4 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/settings/QuestsSettings.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/settings/QuestsSettings.java
@@ -1,6 +1,7 @@
 package net.knarcraft.dynmapcitizens.settings;
 
 import org.bukkit.configuration.file.FileConfiguration;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * All settings for the quests trait
@@ -16,7 +17,7 @@ public class QuestsSettings extends AbstractTraitSettings {
     private final AreaMarkerSettings reachAreaSettings = new AreaMarkerSettings();
 
     @Override
-    public void load(FileConfiguration configuration) {
+    public void load(@NotNull FileConfiguration configuration) {
         super.load(configuration);
         this.displayRewardInfo = configuration.getBoolean(getTraitConfigRoot() + ".displayRewardInfo", true);
         this.displayPlannerInfo = configuration.getBoolean(getTraitConfigRoot() + ".displayPlannerInfo", true);
@@ -28,7 +29,7 @@ public class QuestsSettings extends AbstractTraitSettings {
     }
 
     @Override
-    protected String getTraitConfigRoot() {
+    protected @NotNull String getTraitConfigRoot() {
         return "traits.quests";
     }
 
@@ -82,7 +83,7 @@ public class QuestsSettings extends AbstractTraitSettings {
      *
      * @return <p>Settings for the kill area markers</p>
      */
-    public AreaMarkerSettings getKillAreaSettings() {
+    public @NotNull AreaMarkerSettings getKillAreaSettings() {
         return killAreaSettings;
     }
 
@@ -91,7 +92,7 @@ public class QuestsSettings extends AbstractTraitSettings {
      *
      * @return <p>Settings for the reach area markers</p>
      */
-    public AreaMarkerSettings getReachAreaSettings() {
+    public @NotNull AreaMarkerSettings getReachAreaSettings() {
         return reachAreaSettings;
     }
 
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/settings/SentinelSettings.java b/src/main/java/net/knarcraft/dynmapcitizens/settings/SentinelSettings.java
index 9b4c665..d63b77a 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/settings/SentinelSettings.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/settings/SentinelSettings.java
@@ -1,6 +1,7 @@
 package net.knarcraft.dynmapcitizens.settings;
 
 import org.bukkit.configuration.file.FileConfiguration;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * All settings for the sentinel trait
@@ -10,13 +11,13 @@ public class SentinelSettings extends AbstractTraitSettings {
     private boolean displaySentinelStats;
 
     @Override
-    public void load(FileConfiguration configuration) {
+    public void load(@NotNull FileConfiguration configuration) {
         super.load(configuration);
         displaySentinelStats = configuration.getBoolean(getTraitConfigRoot() + ".displaySentinelStats", true);
     }
 
     @Override
-    protected String getTraitConfigRoot() {
+    protected @NotNull String getTraitConfigRoot() {
         return "traits.sentinel";
     }
 
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/settings/TraitSettings.java b/src/main/java/net/knarcraft/dynmapcitizens/settings/TraitSettings.java
index 58256a8..933839e 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/settings/TraitSettings.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/settings/TraitSettings.java
@@ -1,6 +1,7 @@
 package net.knarcraft.dynmapcitizens.settings;
 
 import org.bukkit.configuration.file.FileConfiguration;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * An interface describing a generic trait settings class
@@ -12,7 +13,7 @@ public interface TraitSettings {
      *
      * @param configuration <p>The configuration to load values from</p>
      */
-    void load(FileConfiguration configuration);
+    void load(@NotNull FileConfiguration configuration);
 
     /**
      * Gets whether this trait type is enabled in the config
@@ -28,14 +29,14 @@ public interface TraitSettings {
      *
      * @return <p>The id of the marker set</p>
      */
-    String getMarkerSetId();
+    @NotNull String getMarkerSetId();
 
     /**
      * Gets the name of this trait's marker set
      *
      * @return <p>The name of the marker set</p>
      */
-    String getMarkerSetName();
+    @NotNull String getMarkerSetName();
 
     /**
      * Gets the priority of the trait's marker set
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/util/DynmapHelper.java b/src/main/java/net/knarcraft/dynmapcitizens/util/DynmapHelper.java
index fbe9990..96e7696 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/util/DynmapHelper.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/util/DynmapHelper.java
@@ -7,6 +7,8 @@ import org.bukkit.World;
 import org.dynmap.DynmapAPI;
 import org.dynmap.markers.CircleMarker;
 import org.dynmap.markers.MarkerSet;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.logging.Level;
 
@@ -20,7 +22,8 @@ public class DynmapHelper {
      * @param label     <p>The label of the marker set if creation is necessary</p>
      * @return <p>The marker set, or null if something went wrong</p>
      */
-    public static MarkerSet getMarkerSet(DynmapAPI dynmapAPI, String setId, String label) {
+    public static @Nullable MarkerSet getMarkerSet(@NotNull DynmapAPI dynmapAPI, @NotNull String setId,
+                                                   @NotNull String label) {
         MarkerSet markerSet = dynmapAPI.getMarkerAPI().getMarkerSet(setId);
         if (markerSet == null) {
             markerSet = dynmapAPI.getMarkerAPI().createMarkerSet(setId, label, null, false);
@@ -41,7 +44,8 @@ public class DynmapHelper {
      * @param markerSettings <p>The settings to use for initialization</p>
      * @return <p>The initialized marker</p>
      */
-    public static MarkerSet initializeMarkerSet(DynmapAPI dynmapAPI, AreaMarkerSettings markerSettings) {
+    public static @Nullable MarkerSet initializeMarkerSet(@NotNull DynmapAPI dynmapAPI,
+                                                          @NotNull AreaMarkerSettings markerSettings) {
         MarkerSet markerSet = DynmapHelper.getMarkerSet(dynmapAPI, markerSettings.getMarkerSetId(),
                 markerSettings.getMarkerSetName());
         if (markerSet != null) {
@@ -60,8 +64,9 @@ public class DynmapHelper {
      * @param markerSet      <p>The marker set to use when marking the location</p>
      * @param markerSettings <p>The settings to use for the marker</p>
      */
-    public static void markLocation(Location location, Integer radius, String description, MarkerSet markerSet,
-                                    AreaMarkerSettings markerSettings) {
+    public static void markLocation(@NotNull Location location, @NotNull Integer radius,
+                                    @NotNull String description, @NotNull MarkerSet markerSet,
+                                    @NotNull AreaMarkerSettings markerSettings) {
         //Skip if location is invalid
         World world = location.getWorld();
         if (world == null) {
@@ -86,7 +91,7 @@ public class DynmapHelper {
      * @param color <p>A hexadecimal color</p>
      * @return <p>An integer representation of the color</p>
      */
-    private static int getColor(String color) {
+    private static int getColor(@NotNull String color) {
         try {
             return Integer.parseInt(color, 16);
         } catch (NumberFormatException exception) {
diff --git a/src/main/java/net/knarcraft/dynmapcitizens/util/QuestsHelper.java b/src/main/java/net/knarcraft/dynmapcitizens/util/QuestsHelper.java
index a29f5d8..0082720 100644
--- a/src/main/java/net/knarcraft/dynmapcitizens/util/QuestsHelper.java
+++ b/src/main/java/net/knarcraft/dynmapcitizens/util/QuestsHelper.java
@@ -4,8 +4,8 @@ import me.blackvein.quests.quests.IQuest;
 import me.blackvein.quests.quests.Planner;
 import net.knarcraft.dynmapcitizens.DynmapCitizens;
 import net.knarcraft.dynmapcitizens.handler.VaultHandler;
-import net.knarcraft.dynmapcitizens.handler.trait.quests.QuestNPCType;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * A helper class for various quests-related tasks
@@ -18,7 +18,7 @@ public class QuestsHelper {
      * @param itemStack <p>The item stack to get the string for</p>
      * @return <p>A string describing the item stack</p>
      */
-    public static String getUpperCasedItemStackString(ItemStack itemStack) {
+    public static @NotNull String getUpperCasedItemStackString(@NotNull ItemStack itemStack) {
         return uppercaseFirst(getItemStackString(itemStack));
     }
 
@@ -28,7 +28,7 @@ public class QuestsHelper {
      * @param itemStack <p>The item stack to print</p>
      * @return <p>The string representation of the item stack</p>
      */
-    public static String getItemStackString(ItemStack itemStack) {
+    public static @NotNull String getItemStackString(@NotNull ItemStack itemStack) {
         return normalizeName(itemStack.getType().name()) + " x " + itemStack.getAmount();
     }
 
@@ -38,7 +38,7 @@ public class QuestsHelper {
      * @param string <p>The string to run on</p>
      * @return <p>The same string, with the first character converted to uppercase</p>
      */
-    private static String uppercaseFirst(String string) {
+    private static @NotNull String uppercaseFirst(@NotNull String string) {
         return string.substring(0, 1).toUpperCase() + string.substring(1);
     }
 
@@ -48,7 +48,7 @@ public class QuestsHelper {
      * @param name <p>The name to normalize</p>
      * @return <p>The normalized name</p>
      */
-    public static String normalizeName(String name) {
+    public static @NotNull String normalizeName(@NotNull String name) {
         return name.toLowerCase().replace("_", " ");
     }
 
@@ -58,7 +58,7 @@ public class QuestsHelper {
      * @param money <p>The amount to pay/use</p>
      * @return <p>The currency name to use</p>
      */
-    public static String getCurrency(double money) {
+    public static @NotNull String getCurrency(double money) {
         VaultHandler vaultHandler = DynmapCitizens.getInstance().getVaultHandler();
         if (vaultHandler.isEnabled()) {
             return vaultHandler.getCurrency(money != 1);
@@ -67,29 +67,13 @@ public class QuestsHelper {
         }
     }
 
-    /**
-     * Gets the marker title to use for the given quest NPC type
-     *
-     * @param type <p>The type of marker to get the title for</p>
-     * @return <p>The title to use for the marker</p>
-     */
-    public static String getMarkerTitle(QuestNPCType type) {
-        return switch (type) {
-            case GIVER -> "Quest Start NPC: ";
-            case INTERACT -> "Quest Interact NPC: ";
-            case DELIVER -> "Quest Deliver NPC: ";
-            case KILL -> "Quest Kill NPC: ";
-            case CHAIN -> "Quest Chain NPC: ";
-        };
-    }
-
     /**
      * Checks whether the given quest is unavailable, according to its planner information
      *
      * @param quest <p>The quest to check for availability</p>
      * @return <p>True if the quest is unavailable</p>
      */
-    public static boolean isQuestUnavailable(IQuest quest) {
+    public static boolean isQuestUnavailable(@NotNull IQuest quest) {
         Planner planner = quest.getPlanner();
         long currentTime = System.currentTimeMillis();