Useful technology emerges from clear decisions about context, responsibility and the way people work. Three considerations for defi & dex.
Treat the quote as temporary
The interface should explain when a quote was obtained and when it needs refreshing. Changes in route or received amount should be visible before signing.
Separate permission from exchange
A token allowance and a swap are different actions. Make approval scope understandable and provide a clear continuation after an allowance transaction completes.
Use explicit failure states
Expired quotes, insufficient balances, rejected signatures and failed execution need different recovery guidance. A generic error message hides the decision the user needs to make.
Start with a workflow you can understand, observe and improve.
These are general design considerations. Implementation depends on the system, users and operational requirements.
Discuss your context