NET LOSS PER SHARE - Antidilutive Securities (Details) - shares	6 Months Ended
	Jul. 31, 2026	Jul. 31, 2025
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities (in shares)	54,337,797	216,787,753
Redeemable convertible preferred shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities (in shares)	0	146,360,207
Stock options issued and outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities (in shares)	31,865,065	41,581,733
RSUs issued and outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities (in shares)	21,737,477	7,771,766
ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities (in shares)	733,515	0
Warrants to purchase redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities (in shares)	0	40,160
Warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities (in shares)	0	1,211,223
Shares of common stock subject to repurchase
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities (in shares)	1,740	21,751
Convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities (in shares)	0	12,273,965
SAFEs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities (in shares)	0	7,526,948