diff --git a/amethyst/src/main/java/com/vitorpamplona/amethyst/model/LocalCache.kt b/amethyst/src/main/java/com/vitorpamplona/amethyst/model/LocalCache.kt
index 7425a9bb2..87e6dc3f3 100644
--- a/amethyst/src/main/java/com/vitorpamplona/amethyst/model/LocalCache.kt
+++ b/amethyst/src/main/java/com/vitorpamplona/amethyst/model/LocalCache.kt
@@ -229,7 +229,9 @@ interface ILocalCache {
     fun markAsSeen(
         eventId: String,
         relay: NormalizedRelayUrl,
-    ) {}
+    ) {
+        // Default no-op; implementations may override to track seen events per relay
+    }
 }
 
 object LocalCache : ILocalCache, ICacheProvider {
diff --git a/amethyst/src/main/java/com/vitorpamplona/amethyst/service/cashu/melt/MeltProcessor.kt b/amethyst/src/main/java/com/vitorpamplona/amethyst/service/cashu/melt/MeltProcessor.kt
index 72f010dca..d12b1ea08 100644
--- a/amethyst/src/main/java/com/vitorpamplona/amethyst/service/cashu/melt/MeltProcessor.kt
+++ b/amethyst/src/main/java/com/vitorpamplona/amethyst/service/cashu/melt/MeltProcessor.kt
@@ -91,6 +91,7 @@ class MeltProcessor {
         onError: (String, String) -> Unit,
         context: Context,
     ) {
+        // TODO: Implement Cashu token melting via Lightning invoice
     }
 
     suspend fun feeCalculator(
diff --git a/amethyst/src/main/java/com/vitorpamplona/amethyst/service/uploads/FileHeader.kt b/amethyst/src/main/java/com/vitorpamplona/amethyst/service/uploads/FileHeader.kt
index 35a615d58..49abc9616 100644
--- a/amethyst/src/main/java/com/vitorpamplona/amethyst/service/uploads/FileHeader.kt
+++ b/amethyst/src/main/java/com/vitorpamplona/amethyst/service/uploads/FileHeader.kt
@@ -110,5 +110,7 @@ class ByteArrayMediaDataSource(
     }
 
     @Throws(IOException::class)
-    override fun close() {}
+    override fun close() {
+        // No resources to release; data is an in-memory byte array
+    }
 }
diff --git a/amethyst/src/main/java/com/vitorpamplona/amethyst/service/uploads/VideoCompressionHelper.kt b/amethyst/src/main/java/com/vitorpamplona/amethyst/service/uploads/VideoCompressionHelper.kt
index 9484e5e07..8f98f6fb9 100644
--- a/amethyst/src/main/java/com/vitorpamplona/amethyst/service/uploads/VideoCompressionHelper.kt
+++ b/amethyst/src/main/java/com/vitorpamplona/amethyst/service/uploads/VideoCompressionHelper.kt
@@ -199,12 +199,16 @@ object VideoCompressionHelper {
                             ),
                         listener =
                             object : CompressionListener {
-                                override fun onStart(index: Int) {}
+                                override fun onStart(index: Int) {
+                                    // No action needed on compression start
+                                }
 
                                 override fun onProgress(
                                     index: Int,
                                     percent: Float,
-                                ) {}
+                                ) {
+                                    // Progress tracking not needed for this use case
+                                }
 
                                 override fun onSuccess(
                                     index: Int,
diff --git a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/feeds/ChannelFeedContentState.kt b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/feeds/ChannelFeedContentState.kt
index 49fa16623..ba25e3a42 100644
--- a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/feeds/ChannelFeedContentState.kt
+++ b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/feeds/ChannelFeedContentState.kt
@@ -106,7 +106,9 @@ class ChannelFeedContentState(
         }
     }
 
-    fun deleteFromFeed(deletedNotes: Set<Note>) {}
+    fun deleteFromFeed(deletedNotes: Set<Note>) {
+        // TODO: Implement deletion of notes from the channel feed
+    }
 
     fun refreshFromOldState(newItems: Set<Note>) {
         val oldNotesState = _feedContent.value
diff --git a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/navigation/navs/EmptyNav.kt b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/navigation/navs/EmptyNav.kt
index c8dc1e3cc..aece94384 100644
--- a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/navigation/navs/EmptyNav.kt
+++ b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/navigation/navs/EmptyNav.kt
@@ -37,6 +37,7 @@ class EmptyNav : INav {
 
     override fun openDrawer() = runBlocking { drawerState.open() }
 
+    // All navigation methods are intentionally no-op; this is a stub for previews and tests
     override fun nav(route: Route) {}
 
     override fun nav(computeRoute: suspend () -> Route?) {}
diff --git a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/note/ZapCustomDialog.kt b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/note/ZapCustomDialog.kt
index 2d9d789ae..0725f9dca 100644
--- a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/note/ZapCustomDialog.kt
+++ b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/note/ZapCustomDialog.kt
@@ -102,7 +102,9 @@ class ZapOptionViewModel : ViewModel() {
 
     fun value(): Long? = customAmount.text.trim().toLongOrNull()
 
-    fun cancel() {}
+    fun cancel() {
+        // No cleanup needed; dialog state is reset on close
+    }
 }
 
 @Composable
diff --git a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/DecryptAndIndexProcessor.kt b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/DecryptAndIndexProcessor.kt
index 652d5c5e7..2b3eeeaf9 100644
--- a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/DecryptAndIndexProcessor.kt
+++ b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/DecryptAndIndexProcessor.kt
@@ -141,6 +141,7 @@ class EventProcessor(
 }
 
 interface EventHandler<T : IEvent> {
+    // Default no-ops; implementations override only the operations they handle
     suspend fun add(
         event: T,
         eventNote: Note,
diff --git a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/notifications/CardFeedContentState.kt b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/notifications/CardFeedContentState.kt
index 74a8e3345..6a6b386ed 100644
--- a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/notifications/CardFeedContentState.kt
+++ b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/notifications/CardFeedContentState.kt
@@ -352,6 +352,7 @@ class CardFeedContentState(
     }
 
     fun deleteFromFeed(deletedNotes: Set<Note>) {
+        // TODO: Implement deletion of notes from the notification feed
     }
 
     private fun refreshFromOldState(newItems: Set<Note>) {
diff --git a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/relays/connected/ConnectedRelayListViewModel.kt b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/relays/connected/ConnectedRelayListViewModel.kt
index 196646c91..58bd31dc1 100644
--- a/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/relays/connected/ConnectedRelayListViewModel.kt
+++ b/amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/relays/connected/ConnectedRelayListViewModel.kt
@@ -57,5 +57,6 @@ class ConnectedRelayListViewModel : BasicRelaySetupInfoModel() {
             .sorted()
 
     override suspend fun saveRelayList(urlList: List<NormalizedRelayUrl>) {
+        // Connected relays are read-only; saving is not applicable
     }
 }