Verify

Validates a buyer's payment against your requirements without moving any money. It decodes the buyer's signed transaction, screens both the payer and your payee address against Chainalysis, checks the amount/ mint/ recipient / fee-payer match what you asked for, and simulate the transaction. Call this before you hand over the protected resource — it's your "is this payment going to work?" check.

Response200 OK — payment is valid

JSON

{
  "isValid": true,
  "payer": "BuyerWalletAddress…"
}

Response200 OK — payment is rejected (still HTTP 200)

JSON

{
  "isValid": false,
  "invalidReason": "invalid_exact_svm_payload_amount_mismatch",
  "payer": "BuyerWalletAddress…"
}

Field	Type	Description
`isValid`	boolean	`true` only if the payment passed screening, requirement checks, and simulation.
`invalidReason`	string	Present when `isValid` is `false`. Machine-readable code (see Reason codes).
`invalidMessage`	string	(optional) Human-readable elaboration on `invalidReason`.
`payer`	string	The buyer's wallet address, when it could be extracted from the transaction.

Error reason codes (non-exhaustive)

Code	Meaning
`sanctioned_address`	Payer or payee flagged by compliance screening.
`screener_unavailable`	Screening provider errored and the facilitator is fail-closed. Retry later.
`fee_payer_not_managed_by_facilitator`	The `extra.feePayer` isn't one of our signers — wrong/stale value from `/supported`.
`invalid_exact_svm_payload_amount_mismatch`	Transaction transfers a different amount than `paymentRequirements.amount`.
`invalid_exact_svm_payload_mint_mismatch`	Transaction uses a different token mint than `asset`.
`invalid_exact_svm_payload_recipient_mismatch`	Transaction pays a different recipient than `payTo`.
`network_mismatch`	Payload network doesn't match requirements.
`transaction_simulation_failed`	The transfer would fail on-chain (e.g. insufficient buyer balance).
`unsupported_scheme`	Scheme isn't registered on this facilitator.
`unexpected_verify_error`	Unhandled internal error.

x402Version

number

enum

required

x402 protocol version. Must be 2; this facilitator does not accept V1.

Allowed:

2

paymentPayload

object

required

x402 V2 payment payload envelope. The inner payload field is scheme-specific; see the examples for each supported (scheme, network) combination.

paymentPayloadobject

paymentRequirements

object

required

x402 V2 payment requirements envelope. The extra field is scheme-specific; see the examples for each supported (scheme, network) combination.

paymentRequirementsobject

``200 Verification result (valid or invalid).

object

isValid

boolean

required

invalidReason

string

invalidMessage

string

payer

string

extensions

object

Has additional fields

extra

object

Has additional fields

``400 Malformed request body.

curl --request POST \
     --url https://api.figment.io/x402/verify \
     --header 'accept: application/json' \
     --header 'content-type: application/json' \
     --header 'x-api-key: your-api-key-here' \
     --data '
{
  "x402Version": 2,
  "paymentPayload": {
    "x402Version": 2
  }
}
'


{
  "isValid": true,
  "invalidReason": "string",
  "invalidMessage": "string",
  "payer": "string",
  "extensions": {},
  "extra": {}
}