Eddie was created by Dr. Light to carry items for Mega Man. (according to US game manuals, Dr. Light built him as his personal cybernetic suitcase) He is equipped with a material transfer unit that allows him to relay an unlimited amount of items from Dr. Light's Laboratory for Mega Man, but because he is incomplete, Eddie is unable to choose items and gives them randomly. Like Rush, Eddie is equipped with a sensor that identifies Mega Man's exact location. The sensor allows him to appear by Mega Man’s side instantly whenever he is needed. He has a jet engine and is able to fly.
- In Mega Man 4 to Mega Man 6 and Mega Man III to Mega Man V, Eddie appears in a section of some stages to help Mega Man, giving a random recovery item.
- In Mega Man & Bass, Rockman & Forte: Mirai Kara no Chousensha, Mega Man 9 and Mega Man 10, Eddie can be bought as an item by Mega Man in the item shop, called Eddie Call (エディコール?) in later games. When he is used, he will teleport in and drop many healing items for Mega Man to pick up. He costs 150 Screws in Mega Man & Bass and in Rockman and Forte: Mirai Kara no Chousensha, 50 Screws in Mega Man 9 and 10 Screws in Mega Man 10.
- In Mega Man: Battle & Chase, Eddie appears only in the loading screen together with Auto, both racing on cars.
- In Mega Man 2: The Power Fighters, Eddie may appear during battles and give a item that calls a support robot. Rush will appear when the item is taken by Mega Man, Treble appears with Bass, and Beat with Proto Man or Duo.
- In Marvel vs. Capcom: Clash of Super Heroes and Marvel vs. Capcom 2: New Age of Heroes, Mega Man and Roll can summon Eddie to give them the Mega Ball, Tornado Hold or Leaf Shield. In the Hyper Combos Hyper Mega Man and Hyper Roll, the user transforms by combining with Rush, Eddie and Beat and performs a powerful attack.
- In the Navi Mode of Rockman Complete Works, Eddie and Beat point recommended directions to the player.
- Eddie appears in Rush's card from SNK vs. Capcom: Card Fighters' Clash.
Big Eddie (ビッグエディ Biggu Edi?), named Eddie's Cybernetic Support Shop in Mega Man 7's US instruction manual, is a giant version of Eddie that is used by Auto and Eddie as a shop in Mega Man 7. The shop can be accessed by pressing the Select button in the stage select screen.
Big Eddie also appeared in the manga Mega Man Gigamix.
Eddie has several appearances in Ruby Spear's Mega Man animated series, where he gives Energy Cans to Mega Man when his energy is low. In the cartoon, Eddie's color scheme was changed from red to green and he also received a small height increase. He can store five Energy Cans in his head.