WeChall does implement the optional script 7.
To poll the latest forum activity, you can call the following script to get them:

https://www.wechall.net/nimda_forum.php?datestamp=20091231232359&limit=10

The output of this script is explained in the optional join documentation.

WeChall does implement an enhanced version for optional script 6.
You are allowed to use it for your own means.

Usage:

https://www.wechall.net/wechall.php?username=Gizmore
Will output the general user ranking on wechall. Usage: username=<username>

https://www.wechall.net/wechall.php?username=!sites%20Gizmore
Will give an overview of all sites the user is linked to. Usage: username=!sites <username>

https://www.wechall.net/wechall.php?username=!TBS%20Gizmore
Will give an overview of one particular site the user is playing. Usage: username="!<site> <username>

To list all possible sites, use https://www.wechall.net/wechall.php?username=!sites.

https://wechall.net/index.php?mo=WeChall&me=API_History&no_session=1&<parameters>

You can poll the latest activities in a machine readable format by using this script.
Usage: https://wechall.net/index.php?mo=WeChall&me=API_History&no_session=1&<parameters>

There are several input parameters for this script
- datestamp [YYYYmmddhhiiss]: fetch only messages >= this datestamp.
- username [WeChall Username]: fetch only messages for one user.
- sitename [Site-name/classname]: fetch only messages for one site.
- limit [max results]: Limit the results to a value.
- masterkey [NoLimit]: Raise the max limit of output rows.
- password [No Api Override for user]: Private API password, when a single user is queried.
- no_session [Mandatory]: You have to put no_session=1 in your requests.

The output format is some sort of csv.
The column separator is :: and the row separator is \n
The char : is escaped with \: and \n is escaped with \\n.
The output columns are:
EventDatestamp::EventType::
WeChallUsername::Sitename::
OnSiteName::OnSiteRank::OnSiteScore::MaxOnSiteScore::OnSitePercent::GainOnsitePercent::
Totalscore::GainTotalscore
- EventDatestamp [YYYYmmddhhiiss]
- EventType [one of link, unlink, gain, lost, ban, unban, unknown]
- WeChallUsername [The Wechall username]
- Sitename [The Sitename or shortcut used on WeChall]
- OnSiteName [The nickname used on the site]
- OnSiteRank [The rank on the site after update]
- OnSiteScore [The score on the site after update]
- MaxOnSiteScore [Max score possible on the site]
- OnSitePercent [The percent solved on the site after update]
- GainOnSitePercent [The percent gained due to this update]
- Totalscore [WeChall Totalscore after update]
- GainTotalscore [WeChall Totalscore gain/loss for update]

Examples:
- ...username=hds
- ...username=hds&limit=50
- ...username=hds&sitename=Yashira
- ...username=hds&sitename=Yashira&datestamp=20100403204635&limit=10

Players can exclude themself from the api calls.
Also players may obfuscate their onsitename and event dates with various settings.
Please note that you will only be able to request the latest 20 activities for a single user, or 50 for all activities.
If you like to pull all or older data you will need a masterkey, given to site admins on demand.

https://wechall.net/index.php?mo=WeChall&me=API_User&no_session=1&username=<username>[&apikey=<your_api_key>]

You can query the UserAPI to get information about a user in a machine readable format.
If you submit your private API password, the result will also include your newlinks-counter, unreadpm-counter and unreadthreads-counter.
The output format is multiple rows in key:value pairs.

Examples:
https://wechall.net/index.php?mo=WeChall&me=API_User&no_session=1&username=Gizmore

https://wechall.net/index.php?mo=WeChall&me=API_Site&no_session=1[&sitename=<sitename>]

You can query the site database with this API to retrieve data in a machine readable format.
The output format is again in CSV, with :: as column and \n as row seperator. : is escaped with \: and \n is escaped with \\n
The output columns are:
Sitename::Classname::Status::URL::ProfileURL::Usercount::Linkcount::Challcount::Basescore::Average::Score

Examples:
https://wechall.net/index.php?mo=WeChall&me=API_Site&no_session=1
https://wechall.net/index.php?mo=WeChall&me=API_Site&no_session=1&sitename=WeChall