The kobold racial trait frost spitter says you exhale a breath of cold air that freezes an area making it difficult terrain. What type of action does it require and how long does the frosted area last?
If an action cost is unspecified, normally doing it requires a standard action.
It refers a white dragon breath, so it is (probably) a supernatural ability and it lasts 1 minute/level (or HD), like the Blizzard version of that.
Or it can last as long as normal frost, from some minutes to days, depending on environmental conditions, if you treat it as a non-magical ability.