Wallet descriptor
A line of text that tells a wallet exactly which addresses are its own: which keys, how they combine and what kind of script. For a multisig wallet, it needs a backup as much as the keys do.
Keys alone don’t always tell a wallet where to look. The same key can make several kinds of bitcoin address, and a multisig wallet’s addresses are made from every key in it and the number that must sign. A descriptor, short for output script descriptor, writes all of that down in one line of text. A two-of-three multisig wallet’s looks like this, with each XPUB standing for one key’s extended public key:
wsh(sortedmulti(2,XPUB1/<0;1>/*,XPUB2/<0;1>/*,XPUB3/<0;1>/*))
It can end with “#” and an eight-character checksum that catches typos.
BIP380, the 2021 standard, explains why descriptors exist: backups that held only private keys couldn’t tell a restored wallet which kinds of addresses to make, so wallets didn’t always agree on what a backup contained. Bitcoin Core made descriptor wallets its default in April 2022, with version 23.0, and since version 30.0, in October 2025, it no longer creates or opens the older kind of wallet, only converts it.
Why it matters
In a single-key wallet, the seed phrase is usually enough. In a multisig wallet it isn’t. A draft standard from 2026, BIP138, puts it plainly: losing the descriptor “is almost as catastrophic as losing the seed itself”, because without it the script can’t be rebuilt, and a lost seed can take its key’s public half with it, leaving the coins out of reach. Bitcoin Core’s own instructions tell everyone who holds a key to keep, and back up, the multisig wallet as well as their own.
So keep a copy of the descriptor with each key. It can’t move money, since it holds no private keys, but it shows every address and balance, so keep it private too.