Attestation

curl --request POST \
  --url https://api.predicate.io/v2/attestation \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --data '
{
  "verification_hash": "x-abc123def456",
  "from": "0x8ba1f109551bD432803012645Hac136c",
  "chain": "ethereum"
}
'

{
  "policy_id": "<string>",
  "policy_name": "<string>",
  "verification_hash": "<string>",
  "is_compliant": true,
  "attestation": {
    "uuid": "<string>",
    "expiration": 123,
    "attester": "<string>",
    "signature": "<string>"
  },
  "reason": {
    "code": "<string>",
    "message": "<string>"
  }
}

POST

attestation

curl --request POST \
  --url https://api.predicate.io/v2/attestation \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --data '
{
  "verification_hash": "x-abc123def456",
  "from": "0x8ba1f109551bD432803012645Hac136c",
  "chain": "ethereum"
}
'

{
  "policy_id": "<string>",
  "policy_name": "<string>",
  "verification_hash": "<string>",
  "is_compliant": true,
  "attestation": {
    "uuid": "<string>",
    "expiration": 123,
    "attester": "<string>",
    "signature": "<string>"
  },
  "reason": {
    "code": "<string>",
    "message": "<string>"
  }
}

Request a compliance attestation for a user. The API evaluates the user against your configured policy and returns a signed attestation.

Request Parameters

Field	Type	Required	Description
`from`	string	Yes	User’s wallet address to evaluate
`chain`	string	Yes	Chain name (see supported chains below)
`verification_hash`	string	Conditional	Your project identifier from the dashboard. Required for offchain integration.
`to`	string	Conditional	Your contract address. Required for onchain integration.
`data`	string	No	Encoded function call data. Required when using `PredicateClient`.
`msg_value`	string	No	Transaction value in wei. Required when using `PredicateClient`.

Use verification_hash for offchain integration (Phase 1). Use to with your contract address for onchain integration (Phase 2).

Supported Chains

Chain	Value
Ethereum	`ethereum`
Base	`base`
Arbitrum	`arbitrum`
Hyperliquid	`hyperliquid`
Plume	`plume`
BSC	`bsc`
Plasma	`plasma`
World	`worldchain`
Sepolia	`sepolia`
Solana	`solana`
Stellar	`stellar`
MegaETH	`megaeth`
MegaETH Testnet	`megaeth-testnet`

Interface-only
Onchain Enforcement

Use verification_hash to evaluate compliance without a deployed contract.

Request

cURL

curl -X POST "https://api.predicate.io/v2/attestation" \
  -H "Content-Type: application/json" \
  -H "x-api-key: $PREDICATE_API_KEY" \
  -d '{
    "verification_hash": "x-abc123def456",
    "from": "0x8ba1f109551bD432803012645Hac136c",
    "chain": "ethereum"
  }'

Response (Compliant)

{
  "policy_id": "policy_abc123def456",
  "policy_name": "Standard AML Compliance",
  "verification_hash": "x-abc123def456",
  "is_compliant": true,
  "attestation": {
    "uuid": "550e8400-e29b-41d4-a716-446655440000",
    "expiration": 1696640400,
    "attester": "0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266",
    "signature": "0x1b2c3d4e..."
  }
}

Response (Non-Compliant)

Some policies return a reason object when the user is not compliant, providing a machine-readable code and a human-readable message explaining why the evaluation failed. Both the code and message values are fully customizable when authoring a policy.

{
  "policy_id": "x-dev-trm-risk-abc123",
  "policy_name": "TRM Risk Score",
  "verification_hash": "x-abc123def456",
  "is_compliant": false,
  "attestation": {
    "uuid": "550e8400-e29b-41d4-a716-446655440000",
    "expiration": 0,
    "attester": "",
    "signature": ""
  },
  "reason": {
    "code": "trm_high_risk",
    "message": "TRM risk score is 10 which exceeds the maximum allowed of 7"
  }
}

Use to with your contract address or program ID for onchain enforcement.

Request (BasicPredicateClient)

cURL

curl -X POST "https://api.predicate.io/v2/attestation" \
  -H "Content-Type: application/json" \
  -H "x-api-key: $PREDICATE_API_KEY" \
  -d '{
    "to": "0x742d35Cc6634C0532925a3b8D4C9db96C4b4d8b6",
    "from": "0x8ba1f109551bD432803012645Hac136c",
    "chain": "base"
  }'

Request (PredicateClient)

Include data and msg_value for policies that validate function calls.

cURL

curl -X POST "https://api.predicate.io/v2/attestation" \
  -H "Content-Type: application/json" \
  -H "x-api-key: $PREDICATE_API_KEY" \
  -d '{
    "to": "0x742d35Cc6634C0532925a3b8D4C9db96C4b4d8b6",
    "from": "0x8ba1f109551bD432803012645Hac136c",
    "data": "0xa9059cbb000000000000000000000000742d35cc6634c0532925a3b8d4c9db96c4b4d8b6",
    "msg_value": "0",
    "chain": "base"
  }'

Response

{
  "policy_id": "policy_abc123def456",
  "policy_name": "Standard AML Compliance",
  "verification_hash": "x-abc123def456",
  "is_compliant": true,
  "attestation": {
    "uuid": "550e8400-e29b-41d4-a716-446655440000",
    "expiration": 1696640400,
    "attester": "0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266",
    "signature": "0x1b2c3d4e..."
  }
}

Request

cURL

curl -X POST "https://api.predicate.io/v2/attestation" \
  -H "Content-Type: application/json" \
  -H "x-api-key: $PREDICATE_API_KEY" \
  -d '{
    "to": "5iejgxCq2vnpiwWpf4qwziVhbX2irmgMEghBrD9tmk5p",
    "from": "8SfpAAUkA4E1ZTSzXiAR51f1iGuVQU4r7kiNUxh7GpVM",
    "chain": "solana"
  }'

Response

{
  "policy_id": "policy_abc123def456",
  "policy_name": "Standard AML Compliance",
  "verification_hash": "x-abc123def456",
  "is_compliant": true,
  "attestation": {
    "uuid": "550e8400-e29b-41d4-a716-446655440000",
    "expiration": 1696640400,
    "attester": "8SfpAAUkA4E1ZTSzXiAR51f1iGuVQU4r7kiNUxh7GpVM",
    "signature": "0x5e4f..."
  }
}

Response Fields

Field	Type	Description
`policy_id`	string	Unique identifier for the policy
`policy_name`	string	Human-readable policy name
`verification_hash`	string	Project identifier
`is_compliant`	boolean	Whether the user passed the policy evaluation
`attestation`	object	Signed attestation to submit onchain
`attestation.uuid`	string	Unique identifier for replay protection
`attestation.expiration`	number	Unix timestamp when the attestation expires
`attestation.attester`	string	Address of the Predicate attester
`attestation.signature`	string	Cryptographic signature
`reason`	object	Present on non-compliant responses when the policy provides a reason. Not included for compliant responses.
`reason.code`	string	Machine-readable error code defined by the policy
`reason.message`	string	Human-readable explanation of why the evaluation failed

Authorizations

x-api-key

string

header

required

Body

application/json

Transaction details to evaluate for policy compliance and to issue a chain-appropriate attestation.

from

string

required

End user's wallet address initiating the transaction. This field is used for policy enforcement and compliance checks.

chain

string

required

Target blockchain name. Examples: ethereum, sepolia, base, solana.

verification_hash

string

Your project identifier from the dashboard. Required for interface-only integration. Use this OR 'to', not both.

string

Your deployed contract or program address. Required for onchain enforcement. Use this OR 'verification_hash', not both.

data

string

Encoded transaction payload. Required when using PredicateClient for function call validation.

msg_value

string

Native token amount (wei for EVM, lamports for Solana). Required when using PredicateClient.

user_ip

string

End-user IP address for geolocation-based policy evaluation.

Response

200 - application/json

Successfully evaluated and returned attestation

Evaluation result and attestation payload to embed onchain.

policy_id

string

Identifier of the evaluated policy.

policy_name

string

Human-readable display name of the policy as configured in the dashboard.

verification_hash

string

Unique value used to prove contract ownership by setting it as the onchain policyID during onboarding.

is_compliant

boolean

True if the request satisfied the configured policy.

attestation

object

Chain‑appropriate attestation fields for onchain verification.

Show child attributes

reason

object

Present on non-compliant responses when the policy provides a reason. Not included for compliant responses.

Show child attributes

⌘I

Essentials

Compliance For

Identity Solution

Request Parameters

Supported Chains

Request

Response (Compliant)

Response (Non-Compliant)

Request (BasicPredicateClient)

Request (PredicateClient)

Response

Request

Response

Response Fields

Authorizations

Body

Response

​Request Parameters

​Supported Chains

​Request

​Response (Compliant)

​Response (Non-Compliant)

​Request (BasicPredicateClient)

​Request (PredicateClient)

​Response

​Request

​Response

​Response Fields

Authorizations

Body

Response

Request Parameters

Supported Chains

Request

Response (Compliant)

Response (Non-Compliant)

Request (BasicPredicateClient)

Request (PredicateClient)

Response

Request

Response

Response Fields