http - YAML media type?

Question

What is the most appropriate media type (formally MIME type) to use when sending data structured with YAML over HTTP and why?

There is no registered application type or text type that I can see.

Example:

> GET /example.yaml

< Content-Type: ????
<
< --- # Favorite movies
< - Casablanca
< - North by Northwest
< - Notorious

Possible options:

• text/x-yaml
• text/yaml
• text/yml
• application/x-yaml
• application/x-yml
• application/yaml
• application/yml

Answer 1

Ruby on Rails uses application/x-yaml with an alternative of text/yaml (source).

I think it's just a matter of convention, there is no technical why, as far as I can tell.