Adventure Game Interpreter
AGI (Adventure Game Interpreter) was the development tool used by Sierra Online to create their early adventure games.
AGI was originally developed by IBM and donated to Sierra to showcase the technology of their PCjr computer.
The first game to use the AGI engine was King's Quest I, released in 1984. An older version of King's Quest IV in AGI was released but it was shortly replaced by a SCI counterpart. There were also a few games made with AGI that were not adventure games.
- Kings Quest 1 - Quest for the Crown 1984
- Kings Quest 2 - Romancing the Throne 1985
- The Black Cauldron 1986
- Donald Duck 1986
- Kings Quest 3 - To Heir is Human 1986
- Mikey's Space Adventure 1986
- Space Quest 1 - The Sarien Encounter 1986
- Winnie The Pooh - In the Hundred-Acre Woods 1986
- Leisure Suit Larry 1 - In the Land of the Lounge Lizards 1987
- Mixed Up Mother Goose 1987
- Police Quest 1 - In pursuit of the Death Angel 1987
- Gold Rush 1988
- Kings Quest 4 - The Perils of Rosella 1988
- Manhunter 1 - New York 1988
- Space Quest 2 - Vohaul's Revenge 1988
- Manhunter 2 - San Francisco 1989
When it was first used, in the mid-1980s, AGI was very innovative and made impressive use of the technology available at the time. Later versions were adapted to use 16 color EGA graphics and the Adlib soundcard.
By the end of the 80s, however, AGI's 160×200 resolution began to look outdated and it couldn't keep up with newer developments such as mice, which were used extensively by the SCUMM engine of competitor Lucasfilm Games. In 1990, Sierra abandoned AGI and started using the SCI (Sierra Creative Interpreter) engine for their adventure games.
Sarien (Sierra AGI resource interpreter engine) is a portable, open-source re-implementation of Sierra's AGI.