diff --git a/packages/opencode/src/provider/transform.ts b/packages/opencode/src/provider/transform.ts
index c2a92e888f..88489a5607 100644
--- a/packages/opencode/src/provider/transform.ts
+++ b/packages/opencode/src/provider/transform.ts
@@ -305,7 +305,7 @@ export namespace ProviderTransform {
     const options: Record<string, any> = {}
 
     if (model.providerID === "openai" || model.api.id.includes("gpt-5")) {
-      if (model.api.id.includes("5.1")) {
+      if (model.api.id.includes("5.")) {
         options["reasoningEffort"] = "low"
       } else {
         options["reasoningEffort"] = "minimal"