Microsoft Agent character

Microsoft Agent was a Windows API, released in 1997 and abandoned by 2003, for creating animated characters (sometimes also called "agents") that would serve as part of a program's interface. It allowed for the creation of new characters, beyond the default provided by Microsoft.

Apparently there was both a "version 1" and "version 2" agent format.

Extensions
Normal character files have the extension ".acs". For distribution online (from when a megabyte download would be too long a wait for most users), characters can be split into .acf files, containing the "core information" of the character; and .aca files, which contain individual animations.

Identification
At least for version 2 files, ACS files begin with and ACF files with ; ACA files apparently begin with a minor version number.

Specifications

 * Unofficial V2 specification

Sample Files

 * Official character downloads
 * Page with direct links
 * The Agentry characters: Characters in ZIP files
 * cami.acs
 * vrgirl.acs
 * Various agents uploaded to the Internet Archive, e.g. Quitter
 * Page listing various (mostly archived) collections of characters
 * https://telparia.com/fileFormatSamples/other/microsoftAgentCharacter/

Software

 * Character and sound editor

Links

 * Web page
 * Microsoft Platform SDK: Microsoft Agent
 * Microsoft Agent web ring
 * Old page
 * Microsoft Agent