diff --git a/codex-rs/core/tests/suite/client.rs b/codex-rs/core/tests/suite/client.rs
index 40664679f5..bacd05e93d 100644
--- a/codex-rs/core/tests/suite/client.rs
+++ b/codex-rs/core/tests/suite/client.rs
@@ -912,6 +912,11 @@ async fn history_dedupes_streamed_and_final_messages_across_turns() {
     // Assert on the last five messages of the input history for request 3.
     // We expect the conversation tail to be [U1, A, U2, A, U3], skipping earlier context and developer messages.
     let r3_tail_expected = serde_json::json!([
+        {
+            "type": "message",
+            "role": "user",
+            "content": [{"type":"input_text","text":"<environment_context>\n  <cwd>/Users/aibrahim/code/codex/codex-rs/core</cwd>\n  <approval_policy>on-request</approval_policy>\n  <sandbox_mode>read-only</sandbox_mode>\n  <network_access>restricted</network_access>\n  <shell>zsh</shell>\n</environment_context>"}]
+        },
         {
             "type": "message",
             "role": "user",
@@ -922,6 +927,11 @@ async fn history_dedupes_streamed_and_final_messages_across_turns() {
             "role": "assistant",
             "content": [{"type":"output_text","text":"Hey there!\n"}]
         },
+        {
+            "type": "message",
+            "role": "user",
+            "content": [{"type":"input_text","text":"<environment_context>\n  <cwd>/Users/aibrahim/code/codex/codex-rs/core</cwd>\n  <approval_policy>on-request</approval_policy>\n  <sandbox_mode>read-only</sandbox_mode>\n  <network_access>restricted</network_access>\n  <shell>zsh</shell>\n</environment_context>"}]
+        },
         {
             "type": "message",
             "role": "user",
@@ -932,6 +942,11 @@ async fn history_dedupes_streamed_and_final_messages_across_turns() {
             "role": "assistant",
             "content": [{"type":"output_text","text":"Hey there!\n"}]
         },
+        {
+            "type": "message",
+            "role": "user",
+            "content": [{"type":"input_text","text":"<environment_context>\n  <cwd>/Users/aibrahim/code/codex/codex-rs/core</cwd>\n  <approval_policy>on-request</approval_policy>\n  <sandbox_mode>read-only</sandbox_mode>\n  <network_access>restricted</network_access>\n  <shell>zsh</shell>\n</environment_context>"}]
+        },
         {
             "type": "message",
             "role": "user",
@@ -939,8 +954,5 @@ async fn history_dedupes_streamed_and_final_messages_across_turns() {
         }
     ]);
 
-    // skipping earlier context and developer messages
-    let tail_len = r3_tail_expected.as_array().unwrap().len();
-    let actual_tail = &r3_input_array[r3_input_array.len() - tail_len..];
-    assert_eq!(serde_json::json!(actual_tail), r3_tail_expected);
+    assert_eq!(serde_json::json!(r3_input_array), r3_tail_expected);
 }