Background

Recently, the LINE business card assistant robot ( linebot-namecard-python ) deployed on Google Cloud Run suddenly went down. After checking the logs with gcloud logging read , the following ruthless error appeared:

google.api_core.exceptions.ResourceExhausted: 429 Your billing account has exceeded its monthly spending cap.

It turned out that we used the API Key provided by Google AI Studio ( google.generativeai package) for rapid development, and as a result, we silently maxed out the monthly free quota.

As a developer who needs to launch a service, it's time to "level up" the architecture and migrate the model calls to the enterprise-grade Google Cloud Vertex AI , directly using GCP's IAM permissions and billing system.…