Sitting tenthh in the World Amateur Golf Rankings, the 18-year-old from Broomieknowe was the top-ranked GB&I player on 21 April, the cut-off for the first of eight berths.
English player Caley McGinty, who, like Darling, played against the Americans at Conwy last year, is the other automatic qualifier.
Darling and McGinty, the world No 11, both made it through to the final round of the Augusta Women’s National Amateur earlier this month.
The final six spots will be filled by captain’s picks, with Elaine Radcliffe revealing her selections next week.
West Kilbride’s Louise Duncan is in the running after being named in the initial squad earlier in the year.
Though she didn’t make that group, Duncan’s fellow Stirling University student Lorna McClymont is also in the frame after winning The R&A Student Tour Series.