Embedding GraphiQL via markdown

Is there a documentation how we can integrate `GraphiQL` in our existing markdown-based documentation?

We`d like to have something like [this](https://github.com/graphql/graphql.github.io/blob/source/src/content/learn/Learn-Queries.md):
```
# { "graphiql": true }
{
hero {
name
}
}
```
Is there a tutorial or something like that on how they did that?