diff --git a/packages/opencode/src/provider/transform.ts b/packages/opencode/src/provider/transform.ts
index dda02cc4..6212edff 100644
--- a/packages/opencode/src/provider/transform.ts
+++ b/packages/opencode/src/provider/transform.ts
@@ -75,7 +75,7 @@ export namespace ProviderTransform {
 
   export function temperature(_providerID: string, modelID: string) {
     if (modelID.toLowerCase().includes("qwen")) return 0.55
-    if (modelID.toLowerCase().includes("claude")) return 1
+    if (modelID.toLowerCase().includes("claude")) return undefined
     return 0
   }