UEML is supported by a set of prototype tools used to maintain and evolve the web of languages. There are currently four tools in the set:

• The UEMLBase? is a Protege-OWL repository that implements the representation meta-meta model described earlier.
• The UEMLBase? Manager is a Java-plugin for Protege-OWL that adds merging, reporting and other housekeeping functions to the repository.
• The UEMLBase? Verifier is a set of Prolog rules and a Prolog rule checker, which together provide formal verification of the UEMLBase? repository.
• The UEMLBase? Analyser uses the repository to compute similarity measures between UEMLBase? constructs, paving the way for consistency checking, automatic update reflection, model-to-model translation across languages, as well as other integrated model uses.