CIP-20

CIP-20 reserves the transaction metadata label 674 for a msg field: an array of UTF-8 strings, each at most 64 bytes, that together form a human-readable message. Splitting the text into 64-byte chunks works around the protocol's per-string metadata limit, and a reader simply joins the pieces back together. The content is purely informational; the ledger never validates or acts on it.

It is the convention exchanges, donation flows, and dApps use to label what a payment is for, and explorers and wallets display it automatically. Note that label 674 is also where the aggregate transaction-message convention lives, so when you tag a transaction's purpose for analytics you attach a specific application label rather than overloading 674 itself, keeping the readable memo separate from machine-readable attribution.