diff --git a/src/tts/tts.ts b/src/tts/tts.ts
index b1177ce5542..8a2200dff32 100644
--- a/src/tts/tts.ts
+++ b/src/tts/tts.ts
@@ -519,6 +519,14 @@ export function isTtsProviderConfigured(config: ResolvedTtsConfig, provider: Tts
   return Boolean(resolveTtsApiKey(config, provider));
 }
 
+function formatTtsProviderError(provider: TtsProvider, err: unknown): string {
+  const error = err instanceof Error ? err : new Error(String(err));
+  if (error.name === "AbortError") {
+    return `${provider}: request timed out`;
+  }
+  return `${provider}: ${error.message}`;
+}
+
 export async function textToSpeech(params: {
   text: string;
   cfg: OpenClawConfig;
@@ -675,12 +683,7 @@ export async function textToSpeech(params: {
         voiceCompatible: output.voiceCompatible,
       };
     } catch (err) {
-      const error = err as Error;
-      if (error.name === "AbortError") {
-        lastError = `${provider}: request timed out`;
-      } else {
-        lastError = `${provider}: ${error.message}`;
-      }
+      lastError = formatTtsProviderError(provider, err);
     }
   }
 
@@ -769,12 +772,7 @@ export async function textToSpeechTelephony(params: {
         sampleRate: output.sampleRate,
       };
     } catch (err) {
-      const error = err as Error;
-      if (error.name === "AbortError") {
-        lastError = `${provider}: request timed out`;
-      } else {
-        lastError = `${provider}: ${error.message}`;
-      }
+      lastError = formatTtsProviderError(provider, err);
     }
   }