diff --git a/codex-rs/memories/write/src/startup_tests.rs b/codex-rs/memories/write/src/startup_tests.rs
index 009b8a6dbe..f80624ac62 100644
--- a/codex-rs/memories/write/src/startup_tests.rs
+++ b/codex-rs/memories/write/src/startup_tests.rs
@@ -897,6 +897,30 @@ async fn run_memory_phase_one_model_request_test(
         contents.push_str(&serde_json::to_string(&line)?);
         contents.push('\n');
     }
+    // Each block exceeds the 8 MiB reader budget, while each record stays below 1 MiB.
+    // Excluded items and ciphertext must not displace the earlier extraction evidence.
+    for item in [
+        json!({"type":"reasoning", "summary":[],
+            "encrypted_content":"r".repeat(/*n*/ 512 * 1024)}),
+        json!({"type":"message", "role":"developer", "content":[
+            {"type":"input_text", "text":"d".repeat(/*n*/ 512 * 1024)},
+        ]}),
+        json!({"type":"message", "role":"assistant", "phase":"final_answer",
+        "encrypted_content":"a".repeat(/*n*/ 512 * 1024), "content":[
+            {"type":"output_text", "text":"small assistant evidence behind ciphertext"},
+        ]}),
+    ] {
+        let line = RolloutLine {
+            timestamp: chrono::Utc::now().to_rfc3339(),
+            ordinal: None,
+            item: RolloutItem::ResponseItem(serde_json::from_value::<ResponseItem>(item)?.into()),
+        };
+        let line = serde_json::to_string(&line)?;
+        for _ in 0..16 {
+            contents.push_str(&line);
+            contents.push('\n');
+        }
+    }
     // Exercise bounded reading through the actual extraction request, for both memory versions.
     contents.push_str(&"x".repeat(1024 * 1024 + 1));
     contents.push('\n');
@@ -949,6 +973,7 @@ async fn run_memory_phase_one_model_request_test(
     let request = wait_for_single_request(&response).await;
     let evidence = request.message_input_texts("user").join("");
     assert!(evidence.contains("replay-bearing assistant evidence"));
+    assert!(evidence.contains("small assistant evidence behind ciphertext"));
     assert!(evidence.contains("newest correction after an oversized record"));
     assert!(!evidence.contains("encrypted_content"));
     if version == codex_protocol::MemoryVersion::V1 {