diff --git a/packages/opencode/src/session/system.ts b/packages/opencode/src/session/system.ts
index 09788f3cdb0e..572c08db58c5 100644
--- a/packages/opencode/src/session/system.ts
+++ b/packages/opencode/src/session/system.ts
@@ -29,7 +29,7 @@ export namespace SystemPrompt {
     if (model.api.id.includes("gemini-")) return [PROMPT_GEMINI]
     if (model.api.id.includes("claude")) return [PROMPT_ANTHROPIC]
     if (model.api.id.toLowerCase().includes("trinity")) return [PROMPT_TRINITY]
-    if (model.api.id.toLowerCase().includes("kimi")) return [PROMPT_KIMI]
+    if (model.api.id.toLowerCase().includes("kimi") || model.api.id.toLowerCase().includes("k2p5")) return [PROMPT_ANTHROPIC]
     return [PROMPT_DEFAULT]
   }