Ignore replayed tool starts

app/androidApp/src/main/kotlin/com/example/aiapp/TranscriptItems.kt

@@ -433,6 +433,13 @@ fun foldEvent(items: List<TranscriptItem>, entry: SeqEvent): List<TranscriptItem
             }
         }
         is SessionEvent.ToolStart ->
+            // A call id names one call for its whole lifetime. Codex can repeat the start while
+            // recovering an in-flight item; appending that replay made two rows with one key, and
+            // Compose aborts the entire LazyColumn when it encounters them. Ignoring the replay
+            // also repairs transcripts which already contain it when they are folded on reopen.
+            if (items.any { it is TranscriptItem.ToolRun && it.id == event.id }) {
+                items
+            } else {
                 items +
                     TranscriptItem.ToolRun(
                         entry.seq,
@@ -443,6 +450,7 @@ fun foldEvent(items: List<TranscriptItem>, entry: SeqEvent): List<TranscriptItem
                         "",
                         done = false,
                     )
+            }
         is SessionEvent.ToolUpdate -> updateTool(items, event.id) { it.copy(output = event.output) }
         is SessionEvent.ToolEnd ->
             // Created when its start is not here, rather than dropped. A fold that only ever

app/androidApp/src/test/kotlin/com/example/aiapp/TranscriptItemsTest.kt

@@ -142,6 +142,23 @@ class TranscriptItemsTest {
         assertTrue(items.none { it is TranscriptItem.TurnBreak }, "$items")
     }
 
+    @Test
+    fun a_repeated_tool_start_is_still_one_row() {
+        val start = SessionEvent.ToolStart("exec-1", "Bash", "{\"command\":\"cargo test\"}")
+        val items =
+            fold(
+                start,
+                SessionEvent.AssistantText("The test run is still going."),
+                start,
+                SessionEvent.ToolEnd("exec-1", "finished"),
+            )
+
+        val tools = items.filterIsInstance<TranscriptItem.ToolRun>()
+        assertEquals(1, tools.size, "$items")
+        assertEquals("finished", tools.single().output)
+        assertTrue(tools.single().done)
+    }
+
     /**
      * The page-join half of the same rule. A boundary that cuts one reply leaves an unfinished half
      * to be rejoined; a boundary that lands between two turns must not join anything, or paging