Individual Verifications — API Reference

The Individual Verifications API enables developers to check whether users have completed specific identity verifications (government ID, phone, biometrics) and query their verification status.

Try out these endpoints interactively in the API Reference Playground .

In the examples below, replace the following placeholder values with your actual data:

{network} - The blockchain network (optimism or base-sepolia)
{address} - The user’s blockchain address
{action-id} - Your action ID for sybil resistance (default: 123456789)

Base URL


https://api.holonym.io

Action IDs

Action IDs enable sybil resistance. Use the default action ID 123456789 for most use cases - it provides universal uniqueness across all applications.

Custom action IDs are available for specific use cases. Contact us to discuss your requirements.

Available Endpoints

Endpoint Action	Endpoint
Check government ID verification	`GET /sybil-resistance/gov-id/{network}`
Check phone verification	`GET /sybil-resistance/phone/{network}`
Check biometrics verification	`GET /sybil-resistance/biometrics/{network}`
Query Proof of Clean Hands attestations	Sign Protocol API
Proof of Clean Hands SBTs (Sui)	`GET /attestation/sbts/clean-hands`

Check Government ID Verification

Returns whether a user has completed government ID (KYC) verification and has a unique proof for the specified action.

GET /sybil-resistance/gov-id/{network}

Query Parameters

Name	Required	Description
`user`	Yes	The user’s blockchain address
`action-id`	Yes	Your action ID for sybil resistance. Use `123456789` for the default action ID, or a custom value for app-specific uniqueness.

Sample request


curl --request GET \
  'https://api.holonym.io/sybil-resistance/gov-id/optimism?user={address}&action-id=123456789'

Sample response (verified)


{
  "result": true,
  "expirationDate": 1770922106
}

Sample response (not verified)


{
  "result": false
}

Response

Field	Type	Description
`result`	boolean	`true` if the user has a valid verification, `false` otherwise
`expirationDate`	number	Unix timestamp when the verification expires (only present when `result` is `true`)

Check Phone Verification

Returns whether a user has completed phone verification and has a unique proof for the specified action.

GET /sybil-resistance/phone/{network}

Query Parameters

Name	Required	Description
`user`	Yes	The user’s blockchain address
`action-id`	Yes	Your action ID for sybil resistance

Sample request


curl --request GET \
  'https://api.holonym.io/sybil-resistance/phone/optimism?user={address}&action-id=123456789'

Sample response (verified)


{
  "result": true,
  "expirationDate": 1770922106
}

Check Biometrics Verification

Returns whether a user has completed biometric verification (face uniqueness and liveness check).

GET /sybil-resistance/biometrics/{network}

Query Parameters

Name	Required	Description
`user`	Yes	The user’s blockchain address
`action-id`	Yes	Your action ID for sybil resistance

Sample request


curl --request GET \
  'https://api.holonym.io/sybil-resistance/biometrics/optimism?user={address}&action-id=123456789'

Sample response (verified)


{
  "result": true,
  "expirationDate": 1780661994
}

Snapshot Strategy Endpoints

These endpoints are designed for integration with Snapshot governance voting.

Configuring Snapshot

To use Individual Verifications with Snapshot, configure the “api” strategy with the following parameters:

Government ID Sybil Resistance


{
  "api": "https://api.holonym.io",
  "symbol": "",
  "decimals": 0,
  "strategy": "snapshot-strategies/sybil-resistance/gov-id",
  "additionalParameters": "action-id=123456789"
}

Phone Sybil Resistance


{
  "api": "https://api.holonym.io",
  "symbol": "",
  "decimals": 0,
  "strategy": "snapshot-strategies/sybil-resistance/phone",
  "additionalParameters": "action-id=123456789"
}

We recommend using the default action ID 123456789. Contact us if you need a custom action ID.

Snapshot: Government ID Sybil Resistance

GET /snapshot-strategies/sybil-resistance/gov-id

Query Parameters

Name	Required	Description
`network`	Yes	Chain ID
`snapshot`	Yes	Block height
`addresses`	Yes	Comma-separated list of blockchain addresses
`action-id`	Yes	Your action ID for sybil resistance

Sample request


curl --request GET \
  'https://api.holonym.io/snapshot-strategies/sybil-resistance/gov-id?network=10&snapshot=12345678&addresses={address1},{address2}&action-id=123456789'

Sample response


{
  "score": [
    { "address": "0x123...", "score": 1 },
    { "address": "0x456...", "score": 0 }
  ]
}

Snapshot: Phone Sybil Resistance

GET /snapshot-strategies/sybil-resistance/phone

Uses the same parameters and response format as the Government ID Snapshot endpoint.

Snapshot: Biometrics Sybil Resistance

GET /snapshot-strategies/sybil-resistance/biometrics

Uses the same parameters and response format as the Government ID Snapshot endpoint.

Proof of Clean Hands (PoCH)

Proof of Clean Hands verification proves that a user is not on sanctions or PEP (Politically Exposed Persons) lists. This enables regulatory compliance while preserving user privacy.

Query Proof of Clean Hands Attestations via Sign Protocol

Proof of Clean Hands attestations are issued through Sign Protocol. Query a user’s attestation status using the Sign Protocol API.

GET https://mainnet-rpc.sign.global/api/scan/addresses/\{address\}/attestations

Sample request


curl --request GET \
  'https://mainnet-rpc.sign.global/api/scan/addresses/{address}/attestations'

Sample response


{
  "data": {
    "rows": [
      {
        "fullSchemaId": "onchain_evm_10_0x8",
        "attester": "0xB1f50c6C34C72346b1229e5C80587D0D659556Fd",
        "isReceiver": true,
        "revoked": false,
        "validUntil": 1735689600
      }
    ]
  }
}

Validating a Proof of Clean Hands Attestation

To confirm a user has a valid Proof of Clean Hands attestation, verify all of the following conditions:

Field	Required Value	Description
`fullSchemaId`	`onchain_evm_10_0x8`	The schema ID for Proof of Clean Hands attestations on Optimism
`attester`	`0xB1f50c6C34C72346b1229e5C80587D0D659556Fd`	The authorized attester address
`isReceiver`	`true`	Confirms the queried address is the attestation recipient
`revoked`	`false`	Attestation has not been revoked
`validUntil`	Greater than current timestamp	Attestation has not expired

Validation example


function hasValidCleanHandsAttestation(attestations: any[]): boolean {
  const now = Math.floor(Date.now() / 1000);
 
  return attestations.some(att =>
    att.fullSchemaId === 'onchain_evm_10_0x8' &&
    att.attester === '0xB1f50c6C34C72346b1229e5C80587D0D659556Fd' &&
    att.isReceiver === true &&
    att.revoked === false &&
    att.validUntil > now
  );
}

Proof of Clean Hands SBTs (Sui)

For Sui blockchain integration, query Proof of Clean Hands SBT status directly.

GET /attestation/sbts/clean-hands

Query Parameters

Name	Required	Description
`address`	Yes	The user’s Sui address
`action-id`	Yes	Your action ID

Sample request


curl --request GET \
  'https://api.holonym.io/attestation/sbts/clean-hands?address={sui_address}&action-id=123456789'

Sample response (verified user)


{
  "isUnique": true,
  "signature": "0x...",
  "circuitId": 12345
}

Sample response (non-verified user)


{
  "isUnique": false
}

Response

Field	Type	Description
`isUnique`	boolean	`true` if the user has a valid Proof of Clean Hands attestation, `false` otherwise
`signature`	string	Cryptographic signature for on-chain verification (only present when `isUnique` is `true`)
`circuitId`	number	The circuit identifier used for the attestation (only present when `isUnique` is `true`)

Proof of Clean Hands verification combines KYC data with AML (Anti-Money Laundering) checks. The user’s identity information is encrypted and can only be decrypted by authorized parties in case of regulatory requirements.

Supported Networks

Network	Path Value	Supported Endpoints
Optimism (Mainnet)	`optimism`	All endpoints
Base Sepolia (Testnet)	`base-sepolia`	All endpoints

For more details on integration patterns, see the Developer Quick Start .