gentoo-overlay/dev-games/hlsdk/metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
<herd>games</herd>
<longdescription>
Half-Life SDK

The current version of the Half-Life SDK is 2.3, which includes new functionality 
for mod authors, greatly increasing their power to create a wide variety of games 
using the Half-Life engine. The new features included with version 2.3 are the 
inclusion of the Ricochet source code (with multi-serve technology), first-person 
spectator code, and updated information on the server query protocol.

Note:
This is the version from metamod ... it's been ported and updated for use in linux.
</longdescription>
</pkgmetadata>