It is recommended, to include contact information in your user-agent header:

    Bad: User-Agent: reqwest/0.9.1
    Better: User-Agent: my_bot
    Best: User-Agent: my_bot (my_bot.com/info) or User-Agent: my_bot (help@my_bot.com)

This allows us to contact you if we would like a change in your application’s behavior without having to block your traffic.