A PERMISSION DENIED error in Vertex AI usually occurs due to insufficient IAM roles, missing API enablement, or incorrect authentication setup, and can be resolved by verifying IAM roles, enabling the Vertex AI API, and ensuring proper authentication
Here is the code snippet you can refer to:

In the above code we are using the following approaches:
- Enables Vertex AI API to ensure the service is accessible.
- Assigns correct IAM roles (aiplatform.user) to grant necessary permissions.
- Uses gcloud auth application-default login to authenticate with valid credentials.
- Verifies IAM policy settings to check if the user has the correct roles.
Hence, resolving PERMISSION DENIED errors in Vertex AI requires ensuring the API is enabled, assigning correct IAM roles, and properly authenticating with Google Cloud.