Signers & recovery
Your smart wallet starts with one key: your login key (the wallet tied to your XDC AI account). That single key is enough to run everything. For stronger protection you can add more keys and require two of them to approve high-value actions - so a single stolen key or a lost device can't move your funds.
Your wallet is a Safe smart account, so these keys are real on-chain owners with a threshold - the number of signatures an action needs.
The keys
| Key | What it is | How you sign |
|---|---|---|
| Login key | The wallet created when you signed in. Always present. | In the browser, automatically. |
| External wallet | A self-custodied wallet you link (MetaMask or any Ethereum wallet). | You connect it and approve the prompt. |
| Passkey | A device passkey - Touch ID, Face ID, or Windows Hello. | Your device biometric signs. |
Signing setups
| Setup | Threshold | Meaning |
|---|---|---|
| Login key only | 1-of-1 | Your login key alone approves everything. (Default.) |
| + External wallet | 2-of-2 | Both your login key and the external wallet must sign. |
| + Passkey backup | 2-of-3 | Any two of the three keys can sign - so losing one key doesn't lock you out. |
What needs two keys - and what doesn't
Hardening protects the big, irreversible actions. It deliberately does not slow down your agent's everyday spending.
| Action | 1-of-1 | Hardened (2-of-2 / 2-of-3) |
|---|---|---|
| Agent payments within your spending limit | Session key | Unchanged - still just the capped session key |
| Changing your spending limit | Login key | Two keys |
| Withdrawing / transferring funds | Login key | Two keys |
| DeFi actions (supply / borrow / repay) | Login key | Two keys |
Your agent's metered payments keep working with a single scoped session key even after you harden, because the on-chain allowance module enforces the spend cap independently of the owner threshold. Only owner actions - moving funds, changing limits, DeFi - require the second signature.
Before you start: turn on 2FA
Adding a second key requires two-factor authentication to be on. If it isn't, the app asks you to enable it first (scan a QR code with any authenticator app), then continue. This makes sure the person adding a key is really you.
Link an external wallet (2-of-2)
- Go to xdcai.tech/account/security and open the External wallet tab.
- Connect the wallet you want to add (MetaMask or any Ethereum wallet).
- Enter your 2FA code.
- Prove you control the external wallet by signing a short message.
- Approve the change with your login key.
Your wallet is now 2-of-2. Back up the external wallet - it is one of the two keys that approve large actions from now on.
Add a passkey backup (2-of-3)
A passkey is a recovery key stored on your device. With it, any two of your three keys can approve - so if you lose one, you are not locked out.
- On the External wallet tab, click Add passkey.
- Confirm with Touch ID, Face ID, or Windows Hello - your device creates the key on the spot.
- Enter your 2FA code.
- If your wallet is already 2-of-2, approve with your external key (the second-signature step below).
The second-signature step
When your wallet is hardened, any owner action (a limit change, a withdrawal, a DeFi action) pauses on a clear "one more signature" screen after your login key signs. There you:
- See which of your keys can co-sign.
- Choose Connect wallet & sign (your external wallet) or Sign with passkey.
- Approve - the action then executes.
Nothing moves on-chain until the second key signs. Gas is sponsored throughout, so you only ever sign, never pay a network fee.
Remove a key
You can unlink the external wallet from the Security tab. That lowers the threshold back to 1-of-1 (your login key alone). You are emailed whenever a key is added or removed, so you always know your wallet's signing setup changed.
For agents
Adding, linking, and co-signing keys are browser-only actions - an agent can't do them, which is exactly what makes them injection-proof. If an agent triggers an owner action on a hardened wallet, it gets a "second signature required" response; tell the user to finish it in their browser. Everyday agent payments within the spending limit are unaffected and need no second key.
Example prompts
- "Add a second wallet to secure my account."
- "Set up a passkey backup for my wallet."
- "How many keys are on my wallet, and what needs two of them?"