Tips to have autocomplete and documentation when you code .gitlab-ci.yml in VSCode:
- Install https://marketplace.visualstudio.com/items?itemName=redhat.vscode-yaml
- Usually it will automatically detect the schema from the filename, otherwise add it explicitly to the first line : "# yaml-language-server: $schema=https://gitlab.com/gitlab-org/gitlab/-/raw/master/app/assets/javascripts/editor/schema/ci.json"
This is true for all schemas available on https://www.schemastore.org.
For #Json or #Yaml (Yaml is just a superset of Json)