atdtool

atdtool is a command-line tools that contacts an After the Deadline language service and displays the errors reported by the service in a format very similar to gcc's.

After the Deadline is a language checker that is able to:

• spell check contextually
• check style
• check grammar

The official server is free for personal use. They provide a free server for commercial use. atdtool can be used with the default server or with a custom one.