diff --git a/src/main/kotlin/com/android/trisolarisserver/component/OpenAIVisionClient.kt b/src/main/kotlin/com/android/trisolarisserver/component/OpenAIVisionClient.kt
index 0ff1ef0..528c38d 100644
--- a/src/main/kotlin/com/android/trisolarisserver/component/OpenAIVisionClient.kt
+++ b/src/main/kotlin/com/android/trisolarisserver/component/OpenAIVisionClient.kt
@@ -7,6 +7,7 @@ import org.springframework.http.HttpHeaders
 import org.springframework.http.MediaType
 import org.springframework.stereotype.Component
 import org.springframework.web.client.RestTemplate
+import org.springframework.web.client.HttpStatusCodeException
 import org.slf4j.LoggerFactory
 
 @Component
@@ -30,6 +31,10 @@ class OpenAIVisionClient(
 
         val payload = mapOf(
             "model" to model,
+            "instructions" to "Read extremely carefully. Reply ONLY the 12 digits or NONE. No extra text.",
+            "temperature" to 0.0,
+            "top_p" to 1.0,
+            "max_output_tokens" to 12,
             "input" to listOf(
                 mapOf(
                     "role" to "user",
@@ -40,7 +45,10 @@ class OpenAIVisionClient(
                         ),
                         mapOf(
                             "type" to "input_image",
-                            "image_url" to imageUrl
+                            "image_url" to mapOf(
+                                "url" to imageUrl,
+                                "detail" to "high"
+                            )
                         )
                     )
                 )
@@ -58,16 +66,31 @@ class OpenAIVisionClient(
             val node = objectMapper.readTree(body)
 
             val outputText = node.path("output_text").asText()
-            if (outputText.isNotBlank()) return outputText
+            if (outputText.isNotBlank()) {
+                logger.info("OpenAI fallback output_text length={}", outputText.trim().length)
+                return outputText
+            }
 
             val outputArray = node.path("output")
             if (outputArray.isArray && outputArray.size() > 0) {
                 val content = outputArray[0].path("content")
                 if (content.isArray && content.size() > 0) {
                     val text = content[0].path("text").asText()
-                    if (text.isNotBlank()) return text
+                    if (text.isNotBlank()) {
+                        logger.info("OpenAI fallback content text length={}", text.trim().length)
+                        return text
+                    }
                 }
             }
+            val errorNode = node.path("error")
+            if (!errorNode.isMissingNode) {
+                val code = errorNode.path("code").asText()
+                val type = errorNode.path("type").asText()
+                logger.warn("OpenAI fallback error code={} type={}", code, type)
+            }
+            null
+        } catch (e: HttpStatusCodeException) {
+            logger.warn("OpenAI fallback HTTP error status={} body={}", e.statusCode.value(), e.responseBodyAsString.take(200))
             null
         } catch (e: Exception) {
             logger.warn("OpenAI fallback failed: {}", e.message)