`async` functions on `docs.rs`

It seems that `async` functions on https://docs.rs/langchain-rust/latest/langchain_rust/output_parsers/struct.MarkdownParser.html are in the expanded form (`impl Future`, etc.).

However, on other crates docs.rs it seems that async can be handled in a less scary way https://docs.rs/ollama-rs/0.1.4/ollama_rs/struct.Ollama.html.

I wonder, why it looks like this. I think showing `async fn` is better than `impl Future<...>`