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Guides
Set up your account and integrate HSA/FSA payments with Flex.
API Reference
Comprehensive API reference for developers using Flex.
Flex MCP
Connect Claude, Cursor, and other AI assistants to your Flex account.
Marketing
Resources and assets to help promote Flex HSA/FSA payments.
Compliance Hub
How Flex determines eligibility, meets IRS substantiation requirements, and works with telehealth partners.
Changelog
Latest updates and improvements to Flex.