diff --git a/relay_rpc/src/jwt.rs b/relay_rpc/src/jwt.rs
index 7bbf3d2..406c467 100644
--- a/relay_rpc/src/jwt.rs
+++ b/relay_rpc/src/jwt.rs
@@ -22,11 +22,20 @@ pub enum JwtError {
     #[error("Invalid JWT signing algorithm")]
     Header,
 
-    #[error("JWT Token is expired")]
-    Expired,
-
-    #[error("JWT Token is not yet valid")]
-    NotYetValid,
+    #[error("JWT Token is expired: {:?}", expiration)]
+    Expired { expiration: Option<i64> },
+
+    #[error(
+        "JWT Token is not yet valid: basic.iat: {}, now + time_leeway: {}, time_leeway: {}",
+        basic_iat,
+        now_time_leeway,
+        time_leeway
+    )]
+    NotYetValid {
+        basic_iat: i64,
+        now_time_leeway: i64,
+        time_leeway: i64,
+    },
 
     #[error("Invalid audience")]
     InvalidAudience,
@@ -202,11 +211,17 @@ pub trait VerifyableClaims: Serialize + DeserializeOwned {
         let now = Utc::now().timestamp();
 
         if matches!(basic.exp, Some(exp) if now - time_leeway > exp) {
-            return Err(JwtError::Expired);
+            return Err(JwtError::Expired {
+                expiration: basic.exp,
+            });
         }
 
         if now + time_leeway < basic.iat {
-            return Err(JwtError::NotYetValid);
+            return Err(JwtError::NotYetValid {
+                basic_iat: basic.iat,
+                now_time_leeway: now + time_leeway,
+                time_leeway,
+            });
         }
 
         if !aud.contains(&basic.aud) {
@@ -278,7 +293,7 @@ mod test {
             .unwrap();
         assert!(matches!(
             Jwt(jwt.into()).decode(&aud),
-            Err(JwtError::NotYetValid)
+            Err(JwtError::NotYetValid { .. })
         ));
 
         // IAT leeway, valid.
@@ -297,7 +312,7 @@ mod test {
             .unwrap();
         assert!(matches!(
             Jwt(jwt.into()).decode(&aud),
-            Err(JwtError::NotYetValid)
+            Err(JwtError::NotYetValid { .. })
         ));
 
         // Past expiration.
@@ -308,7 +323,7 @@ mod test {
             .unwrap();
         assert!(matches!(
             Jwt(jwt.into()).decode(&aud),
-            Err(JwtError::Expired)
+            Err(JwtError::Expired { .. })
         ));
 
         // Expiration leeway, valid.
@@ -333,7 +348,7 @@ mod test {
             .unwrap();
         assert!(matches!(
             Jwt(jwt.into()).decode(&aud),
-            Err(JwtError::Expired)
+            Err(JwtError::Expired { .. })
         ));
 
         // Invalid aud.