Blob bindings can't set ContentType and other properties

The blob output binding feature set always application/octet-stream to ContentType property.
If possible, I would like to modified some blob properties.

And, Just now I don't found documents about some bindings.
Example, Blob output binding can use %rand-guid%. And file name placeholder can use {name} from input binding.

I want to know details about bindings.

Start by reviewing the blob output binding behavior and the existing binding documentation. Check how ContentType and other blob properties are set, and how placeholders such as %rand-guid% and {name} are handled. Done means the requested properties can be configured and the binding details are documented.

Written by the indexing model from the issue text.