diff --git a/tools/mtmd/mtmd.h b/tools/mtmd/mtmd.h
index 8208696807..da4ddaa48e 100644
--- a/tools/mtmd/mtmd.h
+++ b/tools/mtmd/mtmd.h
@@ -334,7 +334,7 @@ enum mtmd_gen_audio_type {
     MTMD_GEN_AUDIO_TYPE_NONE, // not supported
     MTMD_GEN_AUDIO_TYPE_MTP,  // qwen3tts style, with MTP-like generation head
 };
-MTMD_API mtmd_gen_audio_type mtmd_gen_audio_get_type(const mtmd_context * ctx);
+MTMD_API enum mtmd_gen_audio_type mtmd_gen_audio_get_type(const mtmd_context * ctx);
 
 struct mtmd_gen_inp {
     int32_t code0;  // the sampled codebook 0 entry from backbone