Recursion doesn't seem to be working

When I attempt to run my gulp-documentation task, it works fine on the file pointed to as the `src`, but won't recurse into any of my imported files.

Here's the task in question:

```
gulp.task('docs', () => {
return gulp.src('src/init.jsx')
.pipe(documentation({format: 'md', filename: 'api.md'}))
.pipe(gulp.dest('docs'))
})
```

and the command I use to run my gulp task:

```
NODE_PATH=$NODE_PATH:src NODE_ENV=development babel-node ./node_modules/.bin/gulp docs
```