diff --git a/packages/opencode/src/provider/transform.ts b/packages/opencode/src/provider/transform.ts
index 8091f731f0..c5be83a29b 100644
--- a/packages/opencode/src/provider/transform.ts
+++ b/packages/opencode/src/provider/transform.ts
@@ -360,7 +360,7 @@ export namespace ProviderTransform {
 
     switch (model.api.npm) {
       case "@openrouter/ai-sdk-provider":
-        if (!model.id.includes("gpt") && !model.id.includes("gemini-3")) return {}
+        if (!model.id.includes("gpt") && !model.id.includes("gemini-3") && !model.id.includes("claude")) return {}
         return Object.fromEntries(OPENAI_EFFORTS.map((effort) => [effort, { reasoning: { effort } }]))
 
       // TODO: YOU CANNOT SET max_tokens if this is set!!!
@@ -720,6 +720,10 @@ export namespace ProviderTransform {
       result["promptCacheKey"] = input.sessionID
     }
 
+    if (input.model.providerID === "openrouter") {
+      result["prompt_cache_key"] = input.sessionID
+    }
+
     return result
   }