The midfielder put in a strong display in the Republic of Ireland's win over Germany.
Martin O’Neill’s side beat world champions Germany 1-0 on Thursday evening to secure at least a play-off place as they set their sights on Euro 2016 in France next summer.
Shane Long scored the winning goal in the game, meaning he grabbed the headlines from the unlikely victory, but McCarthy played a vital midfield role against the German superstars.
And Sheedy was full of praise for his display, saying it was his best performance in an Ireland shirt.
“I thought James McCarthy was excellent,” he told evertonfc.com.
“I thought it was easily his best game for Ireland. He was superb. We watch him week in, week out doing that for Everton and we know what he’s capable of. He’s shown what he can do for Ireland and he’ll only get confidence from that performance.”
McCarthy is not the only Toffee in the Ireland squad, with Seamus Coleman, Darron Gibson and Aiden McGeady also regulars in Martin O’Neill’s ranks.
None of those played in the win over Germany, but will be keen to take part as the Republic of Ireland take on Poland on Sunday in the final game to contest Group D's second automatic qualification spot.
And while they will have been disappointed to miss out on the starting XI in midweek, Sheedy says having players of that calibre on international duty is a good thing for the Blues.
“Darron and Aiden being on the bench shows that they’re fit and raring to go,” he added.
“It’s difficult to get into the team but they’re ready and waiting – and it can only be good for Everton that we’ve got players of that calibre on international duty and hopefully they’ll get their opportunity soon.”