@olsalas711
There are multiple options:
1. Custom workflow is triggered by dam-authors manually, once the asset is ready.
2. If an asset is published once its ready, then a custom Transport handler can publish the asset info to webservice, while publishing the asset in parallel to AEM publish. https://www.dev-eth0.de/2017/01/08/aem_transport_handler/
3. Create an additional metadata, to define the state of an asset (ready/not-ready). Once all metadata is in, update the value of this metadata to ready. This event can then be captured and info can be sent out to webservice.