YAML and TOML are very commonly used for configuration files nowadays. However, the problem arises in the fact that many of these files have what can be considered their own languages specific to what they are configuring (GitHub Actions for example).

Because of this, the standard of using JSON schemas for validating YAML/TOML files has gained a lot of adoption (trunk has its own schema file as well). Red Hat for example has a very popular VSCode extension for YAML that allows users to identify what schema file is related to a certain YAML file and then provides edit-time validation, node outlining, IntelliSense, and node descriptions.

The JSON schema standard's website has useful information regarding what tools are available for YAML and TOML validation (as well as others) and I believe this would be fairly straight forward to integrate and help everybody using these kinds of config files (most people at this point).