diff --git a/src/core/rpc_log.rs b/src/core/rpc_log.rs
index 35191aefc..674c382ad 100644
--- a/src/core/rpc_log.rs
+++ b/src/core/rpc_log.rs
@@ -82,3 +82,27 @@ fn is_sensitive_key(key: &str) -> bool {
             | "client_secret"
     )
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use serde_json::json;
+
+    #[test]
+    fn test_summarize_rpc_result() {
+        assert_eq!(
+            summarize_rpc_result(&json!({"b": 2, "a": 1})),
+            "object(keys=a,b)"
+        );
+        assert_eq!(summarize_rpc_result(&json!({})), "object(keys=)");
+        assert_eq!(summarize_rpc_result(&json!([1, 2, 3])), "array(len=3)");
+        assert_eq!(summarize_rpc_result(&json!([])), "array(len=0)");
+        assert_eq!(summarize_rpc_result(&json!("hello")), "string(len=5)");
+        assert_eq!(summarize_rpc_result(&json!("")), "string(len=0)");
+        assert_eq!(summarize_rpc_result(&json!(true)), "bool(true)");
+        assert_eq!(summarize_rpc_result(&json!(false)), "bool(false)");
+        assert_eq!(summarize_rpc_result(&json!(42)), "number(42)");
+        assert_eq!(summarize_rpc_result(&json!(3.14)), "number(3.14)");
+        assert_eq!(summarize_rpc_result(&json!(null)), "null");
+    }
+}