From Team Fortress Wiki
- Your Steam API Key
- The user's vanity URL that you would like to retrieve a steam ID for, e.g. http://steamcommunity.com/id/gabelogannewell would use "gabelogannewell"
- The status of the request. 1 if successful, 42 if there was no match.
- steamid (Optional)
- The 64 bit Steam ID the vanity URL resolves to. Not returned on resolution failures.
- message (Optional)
- The message associated with the request status. Currently only used on resolution failures.