diff --git a/packages/openapi-ts/src/plugins/@hey-api/sdk/operation.ts b/packages/openapi-ts/src/plugins/@hey-api/sdk/operation.ts
index 51a7c224cd..c559f4329e 100644
--- a/packages/openapi-ts/src/plugins/@hey-api/sdk/operation.ts
+++ b/packages/openapi-ts/src/plugins/@hey-api/sdk/operation.ts
@@ -130,15 +130,29 @@ export const operationClasses = ({
       }
     }
 
+    // Map path to PascalCase class names
+    const transformedPath = path.map((value) =>
+      operationClassName({
+        context,
+        value,
+      }),
+    );
+
+    // Remove duplicate class names to prevent circular references
+    // Keep only the first occurrence of each class name
+    const uniquePath: Array<string> = [];
+    const seen = new Set<string>();
+    for (const name of transformedPath) {
+      if (!seen.has(name)) {
+        seen.add(name);
+        uniquePath.push(name);
+      }
+    }
+
     classNames.set(rootClass, {
       className: finalClassName,
       methodName: methodName || getOperationMethodName({ operation, plugin }),
-      path: path.map((value) =>
-        operationClassName({
-          context,
-          value,
-        }),
-      ),
+      path: uniquePath,
     });
   }
 
diff --git a/packages/openapi-ts/src/plugins/@hey-api/sdk/plugin.ts b/packages/openapi-ts/src/plugins/@hey-api/sdk/plugin.ts
index f799a89e12..16868a1f69 100644
--- a/packages/openapi-ts/src/plugins/@hey-api/sdk/plugin.ts
+++ b/packages/openapi-ts/src/plugins/@hey-api/sdk/plugin.ts
@@ -179,8 +179,29 @@ const generateClassSdk = ({
             symbolParentClass.placeholder !== symbolCurrentClass.placeholder
           ) {
             const parentClass = sdkClasses.get(symbolParentClass.id)!;
-            parentClass.classes.add(symbolCurrentClass.id);
-            sdkClasses.set(symbolParentClass.id, parentClass);
+            // Check if adding this child would create a cycle
+            // A cycle exists if the current class is an ancestor of the parent class
+            const wouldCreateCycle = (
+              childId: number,
+              ancestorId: number,
+            ): boolean => {
+              const child = sdkClasses.get(childId);
+              if (!child) return false;
+              if (child.id === ancestorId) return true;
+              for (const grandchildId of child.classes) {
+                if (wouldCreateCycle(grandchildId, ancestorId)) {
+                  return true;
+                }
+              }
+              return false;
+            };
+
+            if (
+              !wouldCreateCycle(symbolCurrentClass.id, symbolParentClass.id)
+            ) {
+              parentClass.classes.add(symbolCurrentClass.id);
+              sdkClasses.set(symbolParentClass.id, parentClass);
+            }
           }
         }