Nostr events are always presented in raw form for signing, and I believe it is probably safer to present the raw string for signing too so user can be sure they are not signing something unintended or malicious that might lose them money (eg a bitcoin transaction)

eg, for a Cashu P2PK token, the raw string would be something like:

[\"P2PK\",{\"nonce\":\"859d4935c4907062a6297cf4e663e2835d90d97ecdd510745d32f6816323a41f\",\"data\":\"0249098aa8b9d2fbec49ff8598feb17b592b986e62319a4fa488a3dc36387157a7\",\"tags\":[[\"sigflag\",\"SIG_INPUTS\"]]}]