Fair Value of Financial Assets and Liabilities - Schedule of Fair Value by Balance Sheet Location (Details) - USD ($) $ in Thousands	Jul. 31, 2026	Jan. 31, 2026
Assets
Short-term investments	$ 450,288	$ 410,649
Liabilities
Warrants	0	173,308
U.S. Treasury securities
Assets
Short-term investments	252,173	212,897
Commercial paper
Assets
Short-term investments	6,529	4,601
Corporate bonds
Assets
Short-term investments	191,586	193,151
Fair Value, Recurring \| Level 1
Assets
Total assets	429,944	318,004
Liabilities
Total liabilities		128,363
Fair Value, Recurring \| Level 1 \| Public Warrants
Liabilities
Warrants		128,363
Fair Value, Recurring \| Level 1 \| Private Placement Warrants
Liabilities
Warrants		0
Fair Value, Recurring \| Level 1 \| U.S. Treasury securities
Assets
Short-term investments	252,173	212,897
Fair Value, Recurring \| Level 1 \| Commercial paper
Assets
Short-term investments	0	0
Fair Value, Recurring \| Level 1 \| Corporate bonds
Assets
Cash equivalents	0	0
Short-term investments	0	0
Fair Value, Recurring \| Level 1 \| Money market funds
Assets
Cash equivalents	169,455	99,181
Restricted cash equivalents: money market funds	8,316	5,926
Fair Value, Recurring \| Level 2
Assets
Total assets	198,600	200,336
Liabilities
Total liabilities		0
Fair Value, Recurring \| Level 2 \| Public Warrants
Liabilities
Warrants		0
Fair Value, Recurring \| Level 2 \| Private Placement Warrants
Liabilities
Warrants		0
Fair Value, Recurring \| Level 2 \| U.S. Treasury securities
Assets
Short-term investments	0	0
Fair Value, Recurring \| Level 2 \| Commercial paper
Assets
Short-term investments	6,529	4,601
Fair Value, Recurring \| Level 2 \| Corporate bonds
Assets
Cash equivalents	485	2,584
Short-term investments	191,586	193,151
Fair Value, Recurring \| Level 2 \| Money market funds
Assets
Cash equivalents	0	0
Restricted cash equivalents: money market funds	0	0
Fair Value, Recurring \| Level 3
Assets
Total assets	0	0
Liabilities
Total liabilities		44,945
Fair Value, Recurring \| Level 3 \| Public Warrants
Liabilities
Warrants		0
Fair Value, Recurring \| Level 3 \| Private Placement Warrants
Liabilities
Warrants		44,945
Fair Value, Recurring \| Level 3 \| U.S. Treasury securities
Assets
Short-term investments	0	0
Fair Value, Recurring \| Level 3 \| Commercial paper
Assets
Short-term investments	0	0
Fair Value, Recurring \| Level 3 \| Corporate bonds
Assets
Cash equivalents	0	0
Short-term investments	0	0
Fair Value, Recurring \| Level 3 \| Money market funds
Assets
Cash equivalents	0	0
Restricted cash equivalents: money market funds	$ 0	$ 0

Fair value portion of asset recognized for present right to economic benefit.

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