Devs hate outdated documentation. If a platform you build on changes and doesn’t tell you, it can cause days of frustration and wasted work. So now, when Facebook alters its source code, its developer docs automatically update to stay current. Since Facebook is constantly tinkering with its platform that supports 9 million+ apps, this should make it much easier for developers and keep them loyal.
The full story can be read/found on Developers Will Love This: Facebook Now Auto-Generates Documentation From Source Code