diff --git a/ActivityStore.cs b/ActivityStore.cs
index df400da..b7df2d3 100644
--- a/ActivityStore.cs
+++ b/ActivityStore.cs
@@ -6,11 +6,23 @@ using Object = KristofferStrube.ActivityStreams.Object;
 
 namespace ActivityPub;
 
+/// <summary>
+/// An enum to differentiate inbox and outbox data stores
+/// </summary>
 public enum ActivityStoreType {
+  /// <summary>
+  /// For indicating an Inbox activity store
+  /// </summary>
   Inbox,
+  /// <summary>
+  /// For indicating an Outbox activity store
+  /// </summary>
   Outbox
 }
 
+/// <summary>
+/// A class representing the data store for activities
+/// </summary>
 public class ActivityStore {
   private static Dictionary<string, Activity> _outbox = new();
   private static Dictionary<string, Activity> _inbox = new();
@@ -96,7 +108,7 @@ public class ActivityStore {
   public Activity InsertActivity(Activity newActivity, bool runSideEffects = true, bool runDelivery = true) {
 
     string id = NewId;
-    string uriId = this.Url.AbsoluteRouteUrl(ActivityStoreType == ActivityStoreType.Inbox ? "GetInboxById" : "GetOutboxById", new { id }).ToLower();
+    string? uriId = Url.AbsoluteRouteUrl(ActivityStoreType == ActivityStoreType.Inbox ? "GetInboxById" : "GetOutboxById", new { id })?.ToLower();
     List<Uri> recipients = runDelivery ? ExtractRecipients(newActivity) : new List<Uri>();
     newActivity.Id = uriId;
     newActivity.Bto = newActivity.Bcc = null;
@@ -156,7 +168,7 @@ public class ActivityStore {
       IntransitiveActivity activity = (IntransitiveActivity)newActivity;
       if (activity is Arrive)          return Arrive((Arrive)activity);
       else if (activity is Travel)          return Travel((Travel)activity);
-      // else if (activity is Question)             return Question((Question)activity); // TODO: Temporary until question is intransitory again
+      else if (activity is Question)             return Question((Question)activity);
       else throw new InvalidOperationException($"Activity type '{activity.Type?.FirstOrDefault()}' is unrecognized");
 
     }
@@ -188,7 +200,6 @@ public class ActivityStore {
       else if (activity is TentativeReject) return TentativeReject((TentativeReject)activity);
       else if (activity is TentativeAccept) return TentativeAccept((TentativeAccept)activity);
       else if (activity is View)            return View((View)activity);
-      else if (activity is Question) return Question((Question)activity); // TODO: Temporary until question is intransitory again
       else throw new InvalidOperationException($"Activity type '{activity.Type?.FirstOrDefault()}' is unrecognized");
     }
   }
diff --git a/Constants.cs b/Constants.cs
index 5189a86..55e9216 100644
--- a/Constants.cs
+++ b/Constants.cs
@@ -1,9 +1,18 @@
 namespace ActivityPub;
 
+/// <summary>
+/// The context urls for JSON-LD
+/// </summary>
 public class Context {
+    /// <summary>
+    /// The ActivityStreams context
+    /// </summary>
     public static readonly Uri ActivityStreams = new("https://www.w3.org/ns/activitystreams");
 }
 
+/// <summary>
+/// Known collection urls
+/// </summary>
 public class Collections {
     /// <summary>
     /// The public address for delivery.
diff --git a/Controllers/OutboxController.cs b/Controllers/OutboxController.cs
index eae282d..c03c903 100644
--- a/Controllers/OutboxController.cs
+++ b/Controllers/OutboxController.cs
@@ -26,7 +26,7 @@ public class OutboxController : ControllerBase {
   /// Method to create and process a new object.
   /// See https://www.w3.org/TR/activitypub/#client-to-server-interactions
   /// </summary>
-  /// <param name="newData">The data for the Activity or Object to create</param>
+  /// <param name="newObjectOrLink">The data for the Activity or Object to create</param>
   /// <returns>
   /// 201 (Created) on success with the new id in the Location header
   /// TODO: Also currently returns the newly created Action to assist in debugging.
@@ -44,7 +44,7 @@ public class OutboxController : ControllerBase {
       return this.BadRequest($"No valid Activity or Object found in the request body");
 
     Activity newActivity = (newObjectOrLink is Activity) ? (Activity)newObjectOrLink
-      : Outbox.WrapObjectInCreate(newObjectOrLink as Object);
+      : Outbox.WrapObjectInCreate((Object)newObjectOrLink);
 
     //// Validate the activity
     //try {
diff --git a/ObjectStore.cs b/ObjectStore.cs
index a6859d8..c3a8ae0 100644
--- a/ObjectStore.cs
+++ b/ObjectStore.cs
@@ -7,6 +7,9 @@ using Object = KristofferStrube.ActivityStreams.Object;
 
 namespace ActivityPub;
 
+/// <summary>
+/// A Data layer to store objects
+/// </summary>
 public class ObjectStore {
   private static Dictionary<string, Dictionary<string, Object>> _objects = new();
   private IUrlHelper Url { get; set; }
diff --git a/Repositories/ActivityPubContext.cs b/Repositories/ActivityPubContext.cs
index 3a23096..d08373c 100644
--- a/Repositories/ActivityPubContext.cs
+++ b/Repositories/ActivityPubContext.cs
@@ -43,6 +43,10 @@ public class ActivityPubContext : DbContext {
     options.UseSqlite($"Data Source={DbPath}");
   }
 
+  /// <summary>
+  /// configuration for these models
+  /// </summary>
+  /// <param name="modelBuilder">the model builder to configure</param>
   protected override void OnModelCreating(ModelBuilder modelBuilder) {
     modelBuilder.Entity<Activity>().HasMany(_ => _.Actor as IEnumerable<Actor>);
     modelBuilder.Entity<Activity>().HasMany(_ => _.Object as IEnumerable<ObjectOrLink>);
diff --git a/Types.cs b/Types.cs
index a5da21b..60ce9c1 100644
--- a/Types.cs
+++ b/Types.cs
@@ -185,14 +185,43 @@ public static class Types {
     "Mention"
   ];
 
+  /// <summary>
+  /// Checks if the object type is an activity type
+  /// </summary>
+  /// <param name="type">The type of the object</param>
+  /// <returns>A boolean indicating whether the object is an activity type</returns>
   public static bool IsActivity(string type) => Activity.Contains(type);
   //public static bool IsActivity(this Object obj) => obj.Type == null ? false : IsActivity(obj.Type);
+
+  /// <summary>
+  /// Checks if the object type is an actor type
+  /// </summary>
+  /// <param name="type">The type of the object</param>
+  /// <returns>A boolean indicating whether the object is an actor type</returns>
   public static bool IsActor(string type) => Actor.Contains(type);
   //public static bool IsActor(this Object obj) => obj.Type == null ? false : IsActor(obj.Type);
+
+  /// <summary>
+  /// Checks if the object type is an object type
+  /// </summary>
+  /// <param name="type">The type of the object</param>
+  /// <returns>A boolean indicating whether the object is an object type</returns>
   public static bool IsObject(string type) => Object.Contains(type);
   //public static bool IsObject(this Object obj) => obj.Type == null ? false : IsObject(obj.Type);
+
+  /// <summary>
+  /// Checks if the object type is a link type
+  /// </summary>
+  /// <param name="type">The type of the object</param>
+  /// <returns>A boolean indicating whether the object is a link type</returns>
   public static bool IsLink(string type) => Link.Contains(type);
   //public static bool IsLink(this Object obj) => obj.Type == null ? false : IsLink(obj.Type);
+
+  /// <summary>
+  /// Checks if the object type is an object or link type
+  /// </summary>
+  /// <param name="type">The type of the object</param>
+  /// <returns>A boolean indicating whether the object is an object or link type</returns>
   public static bool IsObjectOrLink(string type) => Object.Concat(Link).Contains(type);
   //public static bool IsObjectOrLink(this Object obj) => obj.Type == null ? false : IsObjectOrLink(obj.Type);
 
diff --git a/Utils/Base36.cs b/Utils/Base36.cs
index cbac40f..0607bb2 100644
--- a/Utils/Base36.cs
+++ b/Utils/Base36.cs
@@ -1,6 +1,9 @@
 namespace ActivityPub.Utils;
 
-// https://stackoverflow.com/a/35004409
+/// <summary>
+/// Helper class for converting numbers to and from Base36 strings
+/// https://stackoverflow.com/a/35004409
+/// </summary>
 public class Base36
 {
     private static readonly char[] BaseChars =
@@ -9,6 +12,11 @@ public class Base36
                .Select((c, i) => new { Char = c, Index = i })
                .ToDictionary(c => c.Char, c => c.Index);
 
+    /// <summary>
+    /// Convert a long to a Base36 string
+    /// </summary>
+    /// <param name="value">The number to convert</param>
+    /// <returns>A string representing the number in Base36</returns>
     public static string ToString(long value)
     {
         long targetBase = BaseChars.Length;
@@ -27,6 +35,11 @@ public class Base36
         return new string(buffer, i, buffer.Length - i);
     }
 
+    /// <summary>
+    /// Converts a Base64 string back into a number
+    /// </summary>
+    /// <param name="number">The string to convert</param>
+    /// <returns>The number resulting from converting the string</returns>
     public static long FromString(string number)
     {
         char[] chrs = number.ToLower().ToCharArray();
diff --git a/Utils/UrlHelperExtensions.cs b/Utils/UrlHelperExtensions.cs
index 8143a65..2b36a92 100644
--- a/Utils/UrlHelperExtensions.cs
+++ b/Utils/UrlHelperExtensions.cs
@@ -16,11 +16,11 @@ public static class UrlHelperExtensions
     /// <param name="controllerName">The name of the controller.</param>
     /// <param name="routeValues">The route values.</param>
     /// <returns>The absolute URL.</returns>
-    public static string AbsoluteAction(
+    public static string? AbsoluteAction(
         this IUrlHelper url,
         string actionName,
         string controllerName,
-        object routeValues = null)
+        object? routeValues = null)
     {
         return url.Action(actionName, controllerName, routeValues, url.ActionContext.HttpContext.Request.Scheme);
     }
@@ -47,10 +47,10 @@ public static class UrlHelperExtensions
     /// <param name="routeName">Name of the route.</param>
     /// <param name="routeValues">The route values.</param>
     /// <returns>The absolute URL.</returns>
-    public static string AbsoluteRouteUrl(
+    public static string? AbsoluteRouteUrl(
         this IUrlHelper url,
         string routeName,
-        object routeValues = null)
+        object? routeValues = null)
     {
         return url.RouteUrl(routeName, routeValues, url.ActionContext.HttpContext.Request.Scheme);
     }
diff --git a/ap.net.csproj b/ap.net.csproj
index c7e5343..0f69b23 100644
--- a/ap.net.csproj
+++ b/ap.net.csproj
@@ -15,7 +15,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="KristofferStrube.ActivityStreams" Version="0.2.2" />
+    <PackageReference Include="KristofferStrube.ActivityStreams" Version="0.2.3" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.InMemory" Version="8.0.3" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="8.0.3" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="8.0.3">