> ## Documentation Index
> Fetch the complete documentation index at: https://pulkit-fix-docs.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Proof of Uniqueness

> Claim a Proof of Uniqueness credential: a one-time face scan that proves you're a real, unique human.

## Why Proof of Uniqueness

Proof of Uniqueness (PoU) verifies that each participant in a project is a real, unique human, not a bot and not one operator running many accounts.

In airdrops, token distributions, and other reward programs, projects want rewards to reach real, contributing users. Bots and Sybil attacks (a single operator running hundreds of accounts) exploit these programs and lead to unfair resource allocation. One face maps to exactly one credential, and one credential maps to exactly one on-chain identity.

## Claim your credential

<Steps>
  <Step title="Open the wallet">
    Open the Billions Wallet (on the web at [wallet.billions.network](https://wallet.billions.network) or through the mobile app) and sign in with Google, Apple ID, or a crypto wallet.
  </Step>

  <Step title="Select the Uniqueness credential">
    From the credentials dashboard, find the **Uniqueness** credential option and select it to start the claim flow.
  </Step>

  <Step title="Complete face verification">
    Follow the on-screen prompts to complete a one-time face scan.
  </Step>

  <Step title="Credential issued">
    Once verification succeeds, the credential is issued directly to your wallet, encrypted, and stored for reuse. You won't need to repeat the face scan: every future request for Proof of Uniqueness, including [linking an AI agent's identity](/agents/identity-skill), reuses this same credential automatically.
  </Step>
</Steps>

<Info>
  If you've already claimed a Proof of Uniqueness credential, any new flow that asks for it (including agent linking) verifies against your existing credential instead of asking you to scan your face again.
</Info>

***

## Troubleshooting

<AccordionGroup>
  <Accordion title="What are the best practices for a successful face scan?">
    For the best results:

    * Use the latest version of the Billions app.
    * Verify in a well-lit environment with a neutral background.
    * Keep your face uncovered: no glasses, headphones, scarves, or hats.
  </Accordion>

  <Accordion title="What does &#x22;Face not unique&#x22; mean?">
    This appears during the claim process when the facial biometrics you provided are already registered to an existing Billions account. Only one Proof of Uniqueness credential can be claimed per person — log in with the original account where your face was first verified instead of claiming a new one.
  </Accordion>
</AccordionGroup>

***

## Learn More

<CardGroup cols={2}>
  <Card title="Verified Agent Identity" icon="link" href="/agents/identity-overview">
    See how this credential is used to verify ownership of an AI agent.
  </Card>

  <Card title="Verified Human" icon="id-card" href="/billions-wallet/verified-human">
    Combine Proof of Uniqueness with document verification for a higher tier of trust.
  </Card>

  <Card title="Verify Proof of Uniqueness" icon="circle-check" href="/billions-wallet/verify-proof-of-uniqueness">
    Add server-side verification to your own app, so you can confirm a user holds this credential.
  </Card>
</CardGroup>


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