diff --git a/quartz/src/main/java/com/vitorpamplona/quartz/experimental/interactiveStories/tags/RootSceneTag.kt b/quartz/src/main/java/com/vitorpamplona/quartz/experimental/interactiveStories/tags/RootSceneTag.kt
index 652d88f62..28cdc8234 100644
--- a/quartz/src/main/java/com/vitorpamplona/quartz/experimental/interactiveStories/tags/RootSceneTag.kt
+++ b/quartz/src/main/java/com/vitorpamplona/quartz/experimental/interactiveStories/tags/RootSceneTag.kt
@@ -25,6 +25,7 @@ import com.vitorpamplona.quartz.nip01Core.core.HexKey
 import com.vitorpamplona.quartz.nip01Core.tags.addressables.Address
 import com.vitorpamplona.quartz.utils.arrayOfNotNull
 import com.vitorpamplona.quartz.utils.bytesUsedInMemory
+import com.vitorpamplona.quartz.utils.ensure
 import com.vitorpamplona.quartz.utils.pointerSizeInBytes
 import com.vitorpamplona.quartz.utils.removeTrailingNullsAndEmptyOthers
 
@@ -66,15 +67,13 @@ data class RootSceneTag(
             dTag: String,
         ) = Address.assemble(kind, pubKeyHex, dTag)
 
-        fun parse(
-            aTagId: String,
-            relay: String?,
-        ) = Address.parse(aTagId)?.let { RootSceneTag(it.kind, it.pubKeyHex, it.dTag, relay) }
-
         @JvmStatic
         fun parse(tag: Array<String>): RootSceneTag? {
-            if (tag.size < TAG_SIZE || tag[0] != TAG_NAME) return null
-            return parse(tag[1], tag.getOrNull(2))
+            ensure(tag.size > 2) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].isNotEmpty()) { return null }
+            val address = Address.parse(tag[1]) ?: return null
+            return RootSceneTag(address.kind, address.pubKeyHex, address.dTag, tag.getOrNull(2))
         }
 
         @JvmStatic
diff --git a/quartz/src/main/java/com/vitorpamplona/quartz/experimental/interactiveStories/tags/StoryOptionTag.kt b/quartz/src/main/java/com/vitorpamplona/quartz/experimental/interactiveStories/tags/StoryOptionTag.kt
index 6327c0527..b664b30f1 100644
--- a/quartz/src/main/java/com/vitorpamplona/quartz/experimental/interactiveStories/tags/StoryOptionTag.kt
+++ b/quartz/src/main/java/com/vitorpamplona/quartz/experimental/interactiveStories/tags/StoryOptionTag.kt
@@ -23,6 +23,7 @@ package com.vitorpamplona.quartz.experimental.interactiveStories.tags
 import com.vitorpamplona.quartz.nip01Core.tags.addressables.Address
 import com.vitorpamplona.quartz.nip46RemoteSigner.getOrNull
 import com.vitorpamplona.quartz.utils.arrayOfNotNull
+import com.vitorpamplona.quartz.utils.ensure
 
 class StoryOptionTag(
     val option: String,
@@ -37,10 +38,10 @@ class StoryOptionTag(
 
         @JvmStatic
         fun parse(tag: Array<String>): StoryOptionTag? {
-            if (tag.size < TAG_SIZE || tag[0] != TAG_NAME) return null
-
+            ensure(tag.size > 3) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[2].isNotEmpty()) { return null }
             val address = Address.parse(tag[2]) ?: return null
-
             return StoryOptionTag(tag[1], address, tag.getOrNull(3))
         }
 
diff --git a/quartz/src/main/java/com/vitorpamplona/quartz/nip01Core/tags/addressables/ATag.kt b/quartz/src/main/java/com/vitorpamplona/quartz/nip01Core/tags/addressables/ATag.kt
index e11d0bd26..91d0a214f 100644
--- a/quartz/src/main/java/com/vitorpamplona/quartz/nip01Core/tags/addressables/ATag.kt
+++ b/quartz/src/main/java/com/vitorpamplona/quartz/nip01Core/tags/addressables/ATag.kt
@@ -28,6 +28,7 @@ import com.vitorpamplona.quartz.nip01Core.core.value
 import com.vitorpamplona.quartz.nip01Core.hints.types.AddressHint
 import com.vitorpamplona.quartz.utils.arrayOfNotNull
 import com.vitorpamplona.quartz.utils.bytesUsedInMemory
+import com.vitorpamplona.quartz.utils.ensure
 import com.vitorpamplona.quartz.utils.pointerSizeInBytes
 import com.vitorpamplona.quartz.utils.removeTrailingNullsAndEmptyOthers
 
@@ -110,31 +111,43 @@ data class ATag(
 
         @JvmStatic
         fun parse(tag: Array<String>): ATag? {
-            if (tag.size < TAG_SIZE || tag[0] != TAG_NAME) return null
+            ensure(tag.size > 2) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].isNotEmpty()) { return null }
             return parse(tag[1], tag.getOrNull(2))
         }
 
         @JvmStatic
         fun parseValidAddress(tag: Array<String>): String? {
-            if (tag.size < TAG_SIZE || tag[0] != TAG_NAME) return null
+            ensure(tag.size > 2) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].isNotEmpty()) { return null }
             return Address.parse(tag[1])?.toValue()
         }
 
         @JvmStatic
         fun parseAddress(tag: Array<String>): Address? {
-            if (tag.size < TAG_SIZE || tag[0] != TAG_NAME) return null
+            ensure(tag.size > 2) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].isNotEmpty()) { return null }
             return Address.parse(tag[1])
         }
 
         @JvmStatic
         fun parseAddressId(tag: Array<String>): String? {
-            if (tag.size < TAG_SIZE || tag[0] != TAG_NAME) return null
+            ensure(tag.size > 2) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].isNotEmpty()) { return null }
             return tag[1]
         }
 
         @JvmStatic
         fun parseAsHint(tag: Array<String>): AddressHint? {
-            if (tag.size < 3 || tag[0] != TAG_NAME || !tag[1].contains(':') || tag[2].isEmpty()) return null
+            ensure(tag.size > 2) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].isNotEmpty()) { return null }
+            ensure(tag[1].contains(':')) { return null }
+            ensure(tag[2].isNotEmpty()) { return null }
             return AddressHint(tag[1], tag[2])
         }
 
diff --git a/quartz/src/main/java/com/vitorpamplona/quartz/nip18Reposts/quotes/QAddressableTag.kt b/quartz/src/main/java/com/vitorpamplona/quartz/nip18Reposts/quotes/QAddressableTag.kt
index fa374d475..355760c17 100644
--- a/quartz/src/main/java/com/vitorpamplona/quartz/nip18Reposts/quotes/QAddressableTag.kt
+++ b/quartz/src/main/java/com/vitorpamplona/quartz/nip18Reposts/quotes/QAddressableTag.kt
@@ -25,6 +25,7 @@ import com.vitorpamplona.quartz.nip01Core.core.HexKey
 import com.vitorpamplona.quartz.nip01Core.tags.addressables.Address
 import com.vitorpamplona.quartz.utils.arrayOfNotNull
 import com.vitorpamplona.quartz.utils.bytesUsedInMemory
+import com.vitorpamplona.quartz.utils.ensure
 import com.vitorpamplona.quartz.utils.pointerSizeInBytes
 
 @Immutable
@@ -61,7 +62,9 @@ data class QAddressableTag(
 
         @JvmStatic
         fun parse(tag: Array<String>): QAddressableTag? {
-            if (tag.size < TAG_SIZE || tag[0] != QTag.TAG_NAME) return null
+            ensure(tag.size > TAG_SIZE) { return null }
+            ensure(tag[0] == QTag.TAG_NAME) { return null }
+            ensure(tag[1].isNotEmpty()) { return null }
             val address = Address.parse(tag[1]) ?: return null
             return QAddressableTag(address, tag.getOrNull(2))
         }
diff --git a/quartz/src/main/java/com/vitorpamplona/quartz/nip89AppHandlers/recommendation/tags/RecommendationTag.kt b/quartz/src/main/java/com/vitorpamplona/quartz/nip89AppHandlers/recommendation/tags/RecommendationTag.kt
index 0b094b2b4..80fdc1f8d 100644
--- a/quartz/src/main/java/com/vitorpamplona/quartz/nip89AppHandlers/recommendation/tags/RecommendationTag.kt
+++ b/quartz/src/main/java/com/vitorpamplona/quartz/nip89AppHandlers/recommendation/tags/RecommendationTag.kt
@@ -26,6 +26,7 @@ import com.vitorpamplona.quartz.nip01Core.core.match
 import com.vitorpamplona.quartz.nip01Core.core.valueIfMatches
 import com.vitorpamplona.quartz.nip01Core.tags.addressables.Address
 import com.vitorpamplona.quartz.utils.arrayOfNotNull
+import com.vitorpamplona.quartz.utils.ensure
 
 @Immutable
 class RecommendationTag(
@@ -44,7 +45,9 @@ class RecommendationTag(
 
         @JvmStatic
         fun parse(tag: Array<String>): RecommendationTag? {
-            if (tag.size < TAG_SIZE || tag[0] != TAG_NAME) return null
+            ensure(tag.size > 2) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].isNotEmpty()) { return null }
             val address = Address.parse(tag[1]) ?: return null
             return RecommendationTag(address, tag.getOrNull(2), tag.getOrNull(3))
         }