Index: src/runtime/ObjFWRT.h
==================================================================
--- src/runtime/ObjFWRT.h
+++ src/runtime/ObjFWRT.h
@@ -242,14 +242,58 @@
     void *_Nullable bytes);
 extern void *_Nullable objc_destructInstance(id _Nullable object);
 extern void *_Null_unspecified objc_autoreleasePoolPush(void);
 extern void objc_autoreleasePoolPop(void *_Null_unspecified pool);
 extern id _Nullable _objc_rootAutorelease(id _Nullable object);
+
+/*!
+ * @brief Sets the tagged pointer secret.
+ *
+ * @param secret A secret, random value that will be used to XOR all tagged
+ *		 pointers with
+ */
 extern void objc_setTaggedPointerSecret(uintptr_t secret);
+
+/*!
+ * @brief Registers a class for tagged pointers.
+ *
+ * @param class The class to register for tagged pointers
+ * @return The tagged pointer ID for the registered class
+ */
 extern int objc_registerTaggedPointerClass(Class _Nonnull class);
+
+/*!
+ * @brief Returns whether the specified object is a tagged pointer.
+ *
+ * @param object The object to inspect
+ * @return Whether the specified object is a tagged pointer
+ */
+static inline bool
+object_isTaggedPointer(id _Nullable object)
+{
+	uintptr_t pointer = (uintptr_t)object;
+
+	return pointer & 1;
+}
+
 extern Class _Nullable object_getTaggedPointerClass(id _Nonnull object);
+
+/*!
+ * @brief Returns the value of the specified tagged pointer.
+ *
+ * @param object The object whose tagged pointer value should be returned
+ * @return The tagged pointer value of the object
+ */
 extern uintptr_t object_getTaggedPointerValue(id _Nonnull object);
+
+/*!
+ * @brief Creates a new tagged pointer.
+ *
+ * @param class The tag ID for the tagged pointer class to use
+ * @param value The value the tagged pointer should have
+ * @return A tagged pointer, or `nil` if it could not be created
+ */
 extern id _Nullable objc_createTaggedPointer(int class, uintptr_t value);
 
 /*
  * Used by the compiler, but can also be called manually.
  *

Index: src/runtime/private.h
==================================================================
--- src/runtime/private.h
+++ src/runtime/private.h
@@ -334,18 +334,10 @@
 
 	return dtable->buckets[i]->buckets[j];
 #endif
 }
 
-static inline bool
-object_isTaggedPointer(id _Nullable object)
-{
-	uintptr_t pointer = (uintptr_t)object;
-
-	return pointer & 1;
-}
-
 #if defined(OF_ELF)
 # if defined(OF_X86_64) || defined(OF_X86) || defined(OF_POWERPC) || \
     defined(OF_ARM64) || defined(OF_ARM) || \
     defined(OF_MIPS64_N64) || defined(OF_MIPS) || \
     defined(OF_SPARC64) || defined(OF_SPARC)