For work I often need to author some YAML. I'm also a neovim nut.
If you find yourself in some similar situation, and you haven't tried it
already, yaml-language-server is epic.
It is easy to setup
with nvim-lspconfig.
Once you have a suitable modeline, such as:
1# yaml-language-server: $schema=https://raw.githubusercontent.com/OpenAssetIO/OpenAssetIO-TraitGen/main/python/openassetio_traitgen/schema.json
Then you get all sorts of lovelyness, such as auto-complete, schema validation and documentation for fields!