diff --git a/packages/opencode/src/provider/transform.ts b/packages/opencode/src/provider/transform.ts
index b177cc2573..90712a131b 100644
--- a/packages/opencode/src/provider/transform.ts
+++ b/packages/opencode/src/provider/transform.ts
@@ -210,7 +210,7 @@ export namespace ProviderTransform {
     //   if (id.includes("thinking")) return 1.0
     //   return 0.6
     // }
-    return 0
+    return undefined
   }
 
   export function topP(model: Provider.Model) {