How can I automatically add alt to images when they are uploaded?

Question

Images

That is, when loading, and not on the fly, for example, by the title of the entry into which the image is loaded.
What would then be the opportunity to edit it (alt).

Answer 1

function set_image_alt_on_upload( $post_ID ) {

  if ( wp_attachment_is_image( $post_ID ) ) {
    
    $attachment = get_post( $post_ID );
    $parent_post = get_post( $attachment->post_parent );

    update_post_meta( $post_ID, '_wp_attachment_image_alt', $parent_post->post_title );
  } 
}
add_action( 'add_attachment', 'set_image_alt_on_upload' );

I wrote from my head and did not test it, but it should work.