Getting build number of dependency build Follow

Simple question, if I have a snapshot dependency setup, so 'B' relies on 'A', and part of the build process for 'A' will set the 'build number' to a custom value, is it possible for 'B' to query what this custom value is?

If not I appreciate I can just write the value into a text file, and upload it as an artifact, but I thought I'd check if this information is already available first.

Steve