diff --git a/packages/opencode/src/provider/provider.ts b/packages/opencode/src/provider/provider.ts
index 9aa1b6304c12..14ea67dbf3cf 100644
--- a/packages/opencode/src/provider/provider.ts
+++ b/packages/opencode/src/provider/provider.ts
@@ -979,7 +979,9 @@ function fromModelsDevModel(provider: ModelsDev.Provider, model: ModelsDev.Model
       npm: model.provider?.npm ?? provider.npm ?? "@ai-sdk/openai-compatible",
     },
     status: model.status ?? "active",
-    headers: {},
+    // Kimi's /coding gateway 429s non-whitelisted User-Agents; model.headers
+    // is spread after the default opencode UA in llm.ts so it takes precedence
+    headers: provider.id === "kimi-for-coding" ? { "User-Agent": "KimiCLI/1.5" } : {},
     options: {},
     cost: cost(model.cost),
     limit: {