diff --git a/codex-rs/core/src/models.rs b/codex-rs/core/src/models.rs
index 326cc97654..fb48b53070 100644
--- a/codex-rs/core/src/models.rs
+++ b/codex-rs/core/src/models.rs
@@ -138,7 +138,7 @@ pub enum ReasoningItemReasoningSummary {
     SummaryText { text: String },
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
 #[serde(tag = "type", rename_all = "snake_case")]
 pub enum ReasoningItemContent {
     ReasoningText { text: String },