Hello Rajender,
You are right, but i was able to get a working tool set using a local Swager-Editor, a local Swagger-UI and an 3rd part editor like sublimeText.
In sublime text you can edit your documentation and quickly see changes in Swagger-UI.
I use local swagger-editor only for validating purpose and to convert YAML to JSON, and reverse.
To have a more efficient editor, the best approach to me, could be to have a sublimeText extension or an Eclipse plugin. This way you can basically grab all
advantages of those tools.
Regards,