Hey Yoann Rodière, thanks for the report and the thorough analysis!

IndexedTypeDescriptor et al. form a public meta-data API (which indeed does not appear to contain information on embedded fields), whereas TypeMetadata etc. are the internal meta-data model and provide the required information.

I am not quite clear why the DSL implementation doesn't use the internal API, maybe Hardy Ferentschik can shed some light on this? On first thought I'd say let's use the internal API. Exposing the embedded information in the public API would be nice, too, but it seems a separate issue which probably should better be addressed separately from fixing this bug.