API Reference: Delegated Contract Mode

API Configurations

Base URLs

The API is deployed across different environments. Please use the appropriate base URL for your integration stage .

Environment	Base URL
Testnet	https://uropenapi.s7.gomantle.org
Production	https://openapi.ur.app

API Authentication

The authentication method for the following Core Banking APIs refers to this document.

User Onboarding Process

Authorization URL Construction

Partner directly constructs the authorization URL without needing to call an API beforehand. When users click the link, they will enter the UR authorization page to complete identity verification and authorization.

Authorization URL Format

https://get.ur.app/auth/authorize?partner_id={partner_id}&redirect_uri={callback_url}&scope={scopes}&state={custom_state}&response_type=code

URL Parameter Description

Parameter	Required	Description	Example
partner_id	Yes	ID generated by UR for the Partner	""
redirect_uri	Yes	Callback address after authorization completion, must be pre-registered with UR	https://partner.com/callback
scope	No	Requested permission scopes, multiple scopes separated by spaces (URL encoding required)	allowance.mantle.USDC%20allowance.mantle.USD24
state	No	Partner custom state parameter for CSRF attack prevention and business information tracking. UR doesn't parse this value, only returns it as-is during redirection	A random string you provide to verify against CSRF attacks. The length of this string can be up to 500 characters.
response_type	Yes	Fixed value: code (authorization code mode)	code

Key Design

• No need to call API beforehand: Partner directly constructs URL, reducing integration complexity

• partner_id: UR identifies Partner through partner_id and confirms identity through signature when verifying code later

• state is completely customizable: Random string to prevent CSRF

• Similar to standard authorization flow: Developers don't need to learn a new authorization pattern

Available Scopes

Scope	Description
allowance.mantle.USDC	USDC authorization on Mantle chain
allowance.mantle.USD24	USD authorization on Mantle chain
allowance.mantle.EUR24	EUR authorization on Mantle chain
allowance.mantle.CHF24	CHF authorization on Mantle chain
allowance.mantle.CNH24	CNH authorization on Mantle chain
allowance.mantle.SGD24	SGD authorization on Mantle chain
allowance.mantle.HKD24	HKD authorization on Mantle chain
allowance.mantle.JPY24	JPY authorization on Mantle chain
allowance.bsc.USDC	USDC authorization on BSC chain
card	Card issuance

User Completes Authorization

After the user clicks the authorization link, they will enter the UR authorization page to complete KYC and authorization operations. After authorization is complete, UR will redirect back to the Partner's redirect_uri with the authorization code code and state parameters.

Redirect URL Format

{redirect_uri}?code={authorization_code}&state={original_state}

Parameter Description

Parameter	Description	Example
code	Authorization code, Partner uses this code to exchange for user information (one-time use, valid for 5 minutes)	UAC_a1b2c3d4e5f6g7h8i9j0
state	Returns the state parameter provided by Partner in step one as-is	""

Redirect Example

Assuming the Partner set redirect_uri to https://partner.example.com/oauth/callback in step one, after the user completes authorization, the browser will redirect to:

https://partner.example.com/oauth/callback?code=UAC_a1b2c3d4e5f6g7h8i9j0&state={state}

Partner Callback Handling Example

// Partner's callback endpoint GET /oauth/callback
app.get('/oauth/callback', (req, res) => {
  const { code, state } = req.query;

  // 1. Verify state parameter to prevent CSRF attacks
  const stateData = JSON.parse(decodeURIComponent(state));
  console.log("Business information:", stateData);
  // { sourceId: 'mobile-app', campaign: 'spring-2024', userId: 'internal-user-12345' }

  // 2. Use code to call UR API to exchange for user information (see step three)
  // ...

  res.send("Authorization successful, processing...");
});

Partner to Fetch User Onboarding Information

After receiving the authorization code code, Partner calls the UR API to exchange for the user's UR identity and authorization information. This step requires Ethereum signature verification of Partner identity. For detailed signing and verification rules, please refer to Signature and Verification.

Field Description:

• userId: UR user ID

• userAddress: User's Ethereum address

• scope: Granted permission scopes

• state: Returns the state parameter provided by Partner as-is

• authorizedAt: Authorization completion timestamp (Unix timestamp)

Error Response:

{
  "code": 4001,
  "message": "Invalid or expired authorization code",
  "data": null
}

Public Data Structures

TransactionData

Transaction data structure used in /v1/transactions, /v1/transaction/query, and webhook.event.transaction.

Complete Example (based on actual API response):

{
  "urId": "7639951412",
  "title": "usd",
  "subtitle": "eip155:5003 USDC 12",
  "amount": "+11.94",
  "type": "CTU",
  "timestamp": 1768659501,
  "image": "",
  "currency": "usd",
  "direction": "IN",
  "txHash": "0x21b4dfa7be02b4e806cf8bc5469ef6af35c76afa6fbace2826c9f8afb2e06cc6",
  "inputChainId": "eip155:5003",
  "inputToken": "USDC",
  "inputAmount": "12",
  "inputTokenAddress": "0xe6a2802837da44f880f52c1681b6740db208755c",
  "outputAmount": "",
  "mcc": 0,
  "reference": "",
  "status": "",
  "bankAccount": "",
  "crdMultiToken": null,
  "ctuExternalSender": "0x96e023fb9b446a65273a0c01cdafdf26b5f21b3f",
  "token": "",
  "tokenAddress": "",
  "fromAddress": "",
  "toAddress": "",
  "statusCode": "",
  "crdCurrency": "",
  "listingTitle": "",
  "txHashUrl": "https://sepolia.mantlescan.xyz/tx/0x21b4dfa7be02b4e806cf8bc5469ef6af35c76afa6fbace2826c9f8afb2e06cc6",
  "txIdIcon": "",
  "officialName": "",
  "partnerRefId": ""
}

Field Descriptions:

Field	Type	Required	Description
urId	string	Yes	UR user ID (string format)
title	string	Yes	Transaction title (for display)
subtitle	string	Yes	Transaction subtitle (e.g., counterparty UR ID, merchant name, chain info, etc.)
amount	string	Yes	Transaction amount (display format with decimals, e.g., "+11.94"), with sign indicating direction
type	string	Yes	Transaction type abbreviation: CTU (cross-chain transfer in), FRX (forex exchange), CTF (crypto transfer), ONR (onramp), CRD (card payment), CDP (deposit), CWP (withdrawal), CWD (withdrawal refund), UNKNOWN
timestamp	int64	Yes	Transaction timestamp (Unix seconds)
image	string	No	Transaction display icon URL or card logo
currency	string	Yes	Currency identifier (lowercase format, e.g., "usd", "eur")
direction	string	Yes	Transaction direction: IN (credit) / OUT (debit)
txHash	string	Yes	On-chain transaction hash (0x prefix)
inputChainId	string	No	Input chain ID (CAIP-2 format, e.g., eip155:5003 for Mantle Sepolia testnet)
inputToken	string	No	Input token symbol
inputAmount	string	No	Input amount (integer string in smallest on-chain unit, e.g., "12")
inputTokenAddress	string	No	Input token contract address (lowercase with 0x prefix)
outputAmount	string	No	Output amount (for exchange transactions, smallest on-chain unit)
mcc	uint64	No	Merchant category code (card payment transactions only)
reference	string	No	Transaction reference number
status	string	No	Transaction status: pending/completed/rejected/unknown. Empty string if status is unknown or not applicable
bankAccount	string	No	Bank account information
crdMultiToken	array	No	Card payment multi-token deduction details (array of {token: string, amount: string})
ctuExternalSender	string	No	External sender address for cross-chain transfer-in transactions (lowercase with 0x prefix)
token	string	No	Token symbol
tokenAddress	string	No	Token contract address
fromAddress	string	No	Sender address
toAddress	string	No	Recipient address
statusCode	string	No	Detailed status code
crdCurrency	string	No	Card payment original currency
listingTitle	string	No	Display title
txHashUrl	string	No	Blockchain explorer link
txIdIcon	string	No	Transaction icon URL
officialName	string	No	Official name
partnerRefId	string	No	Partner custom reference ID (e.g., partner's order number)

Key Field Format Notes:

• urId: Always returned as a string, not a number

• amount: Display format with sign and decimals (e.g., "+11.94", "-6.00")

• currency: Lowercase format (e.g., "usd", "eur", not "USD" or "EUR")

• inputAmount: Integer string representing smallest on-chain unit (e.g., "12" for USDC means 0.000012 USDC with 6 decimals)

• txHashUrl: Complete blockchain explorer URL for the transaction

• Optional fields: May be empty string or omitted depending on transaction type

Chain ID Reference

The chainId field in API requests uses the CAIP-2 standard format eip155:<chainId>, supporting the following chains:

Mantle Chain:

• Testnet: eip155:5003 (Mantle Sepolia Testnet)

• Mainnet: eip155:5000 (Mantle Mainnet)

BSC Chain:

• Testnet: eip155:97 (BSC Testnet)

• Mainnet: eip155:56 (BSC Mainnet)

Important Notes:

• If chainId is not specified in the request, it defaults to Mantle chain

• Cross-chain deposits (e.g., from BSC) require explicit chainId and userAddress parameters

• CAIP-2 format example: eip155:97 represents BSC Testnet (chain ID 97)

Unified amount field description

Unified amount field description: All amount-related request fields named amount, minAmount, maxAmount, minUsdcOut, feeAmount, minAmountOut, etc., use the string type and are converted to the smallest on-chain unit based on the token's decimals (integers only). For example, for USD (decimals=2), 5.00 should be sent as "500"; for USDC (decimals=6), 1.23 should be sent as "1230000".

Core Banking APIs

Mint UR NFT

Refers to this open API.

Card

Webview URL: https://get.ur.app/partner-login?partnerId=[Your PartnerId]&feature=card

By opening this URL, users can activate, view, and manage their card.

Profile

Webview Url: https://get.ur.app/partner-login?partnerId=[Your PartnerId]&feature=profile

By logging in to this URL, users can view their personal information, including Name, IBAN, Address, Bank Name, and BIC/SWIFT.

profile-demo

Fetch UR Account Information

Refers to this open API.

Fetch UR Account Balance

Refers to this open API.

Get Supported Asset List

Endpoint: GET /v1/tokens

Partners can fetch the token list currently configured by UR for this partner (including on-chain precision and display precision), synchronized in real time with on-chain chaincontractconfig.

Request Parameters: None (GET request, no request body required).

Response Example:

{
  "code": 0,
  "message": "",
  "data": [
    {
      "symbol": "USD",
      "name": "USD24",
      "address": "0xdf79470986629ae4893BfCE0c6C0F4d085E99741",
      "decimals": 2,
      "displayDecimals": 2,
      "isFiat": true
    },
    {
      "symbol": "USDC",
      "name": "USD Coin",
      "address": "0xe6a2802837da44F880f52c1681b6740db208755C",
      "decimals": 6,
      "displayDecimals": 2,
      "isFiat": false
    }
  ]
}

Response Field Description:

• symbol: Token symbol

• name: Token full name

• address: Token contract address

• decimals: On-chain smallest unit precision (10^decimals)

• displayDecimals: Recommended frontend display precision (can differ from decimals, e.g., 6 on-chain, 2 for display)

• isFiat: Whether it's a fiat token

• Token order follows on-chain configured priority, alphabetically by symbol if priority is the same.

Fetch Currency Exchange Rate

POST /v1/exchangeRate

Get the exchange rate for the given asset pair.

Request Parameters:

{
  "inSymbol": "EUR",
  "outSymbol": "USD"
}

Field	Type	Required	Description
inSymbol	string	Yes	Input token
outSymbol	string	Yes	Output token

Response Example:

{
  "code": 0,
  "message": "",
  "data": {
    "rate": "0.998",
    "exchangeSpread": "0.002"
  }
}

Response Field Description:

• rate: Exchange rate

• exchangeSpread: Exchange rate spread

Currency Exchange

POST /v1/exchange

User exchange endpoint.

Request Parameters:

{
  "urId": 12345,
  "inputToken": "USD",
  "outputToken": "EUR",
  "amount": "10000",
  "requestId": "req-20240101-0001"
}

Field	Type	Required	Description
urId	int64	Yes	UR user ID
inputToken	string	Yes	Input token, use symbol returned by /v1/tokens
outputToken	string	Yes	Output token, use symbol returned by /v1/tokens
amount	string	Yes	Exchange amount, on-chain smallest unit string (e.g., 100.00 USD => 10000)
requestId	string	Yes	Request idempotency ID (client-defined, for idempotency and troubleshooting)

Response Example:

{
  "code": 0,
  "message": "",
  "data": {
    "txHash": "0x1234567890abcdef..."
  }
}

Response Field Description:

• txHash: Transaction hash

Fetch Transaction History

Refers to this open API.

Fetch Offramp Quote

POST /v1/deposit/quote

Returns fees, exchange rates, and estimated receipt amount for Fiat deposit scenarios. The current version supports direct deposits of Mantle-chain USDC to fiat tokens (USD, EUR, CHF, etc.).

Request Parameters:

{
  "urId": 12345,
  "fromToken": "USDC",
  "toToken": "USD",
  "amount": "3000000",
  "chainId": "eip155:97",
  "userAddress": "0x1234567890abcdef..."
}

Field	Type	Required	Description
urId	int64	Yes	UR user ID
fromToken	string	Yes	Input token symbol (currently only supports USDC), available symbol can be obtained from /v1/tokens
toToken	string	Yes	Target tiat token (USD, EUR, etc.), use symbol returned by /v1/tokens
amount	string	Yes	Input amount in smallest on-chain unit (USDC has 6 decimals: 3000000 = 3 USDC). Minimum: 3 USDC
chainId	string	No	Source chain ID in CAIP-2 format (e.g., eip155:5003 for Mantle Sepolia, eip155:97 for BSC Testnet). Defaults to Mantle chain if not specified
userAddress	string	No	User's UR account address (required when the user deposits from non-Mantle chains)

Response Example:

{
  "code": 0,
  "message": "",
  "data": {
    "feeAmountViaUsdc": "0.50",
    "outputAmount": "999.50",
    "outputAmountBeforeFee": "1000.00",
    "exchangeRate": "1.0",
    "crossChainFee": "0",
    "best": {
      "aggregator": "ur",
      "to": "0x...",
      "swapCalldata": "0x",
      "minUsdcAmount": "990000",
      "expectedUsdcAmount": "1000000",
      "slippageBps": 50,
      "deadline": 1703123600,
      "priceImpact": "0"
    },
    "feeAmountViaNativeToken": "0",
    "processingFee": "0.50",
    "networkFee": "0",
    "totalFee": "0.50",
    "allQuotes": [],
    "chainId": "eip155:5000"
  }
}

Response Field Description:

Field	Type	Description
feeAmountViaUsdc	string	Network gas fee (USDC denominated, decimal string, e.g., 0.05 means 0.05 USDC)
outputAmount	string	Final amount user will receive in target token (decimal string, after all fees and spread)
exchangeRate	string	Exchange rate from input fromToken to toToken
crossChainFee	string	Cross-chain LayerZero fee in native token's smallest unit (e.g., wei for ETH, only applicable for non-Mantle chains)
feeAmountViaNativeToken	string	Fee in native token
processingFee	string	Processing fee
networkFee	string	Network fee
totalFee	string	Total fee
chainId	string	Chain ID
allQuotes	array	All available quotes. If it is USDC, ignore this field.
best	object	Best quote details. If it is USDC, ignore this field.

Important Notes:

• amount must be at least 3 USDC (3000000 in smallest unit)

• The actual output amount deducts multiple fees: network fee (~0.05 USDC), processing fee (~0.5% of deposit), and spread adjustment

• For cross-chain deposits (BSC, etc.), crossChainFee shows the LayerZero bridge fee in native token units

• If amount is below minimum or toToken is not configured on-chain, error code 20003 will be returned

Create Offramp Request

POST /v1/deposit

User deposit endpoint.

Request Parameters:

{
  "urId": 12345,
  "inputToken": "USDC",
  "outputToken": "USD",
  "amount": "3000000",
  "requestId": "deposit-202401010001",
  "chainId": "eip155:97",
  "userAddress": "0x1234567890abcdef..."
}

Field	Type	Required	Description
urId	int64	Yes	UR user ID
inputToken	string	Yes	Input token (only supports USDC), available symbol can be obtained from /v1/tokens
outputToken	string	Yes	Output token (fiat token), use symbol returned by /v1/tokens
amount	string	Yes	Deposit amount in smallest on-chain unit (e.g., 3 USDC = 3000000). Minimum: 3 USDC
requestId	string	Yes	Idempotent request ID, must remain the same on retry
chainId	string	No	Source chain ID in CAIP-2 format (e.g., eip155:5003 for Mantle Sepolia, eip155:97 for BSC Testnet). Defaults to Mantle if not specified
userAddress	string	No	User's wallet address (required for cross-chain deposits from non-Mantle chains)

Response Example:

{
  "code": 0,
  "message": "",
  "data": {
    "txHash": "0x1234567890abcdef..."
  }
}

Response Field Description:

• txHash: Transaction hash

Important Notes:

• requestId must be globally unique and reused on retry to ensure idempotency

• amount must be at least 3 USDC (3000000 in smallest unit)

• Currently supports USDC → Fiat token deposits from Mantle and BSC chains

• For BSC deposits, userAddress is required for cross-chain fee calculation

Create Onramp Request

POST /v1/onramp

Exchanges a fiat token to USDC and (optionally) performs a swap/bridge to the target token based on the quote from /v1/onramp/quote.

Request Parameters

{
  "quoteId": "onramp_1700000000000000000",
  "requestId": "onramp-demo-001",
  "urId": 7639951412,
  "chainId": "eip155:5000",
  "tokenIn": "USD",
  "amountIn": "10000",
  "withdrawAddress": "0xUserWithdrawAddress",
  "dstChainId": "eip155:8453",
  "dstAggregator": "0xAggregatorAddress",
  "dstTokenOut": "USDC",
  "dstSwapCalldata": "0xabcdef...",
  "dstMinAmountOut": "99000000"
}

Field	Type	Required	Description
quoteId	string	Yes	Quote ID returned by /v1/onramp/quote
requestId	string	Yes	Idempotent request ID, reuse on retry
urId	int64	Yes	UR user ID
tokenIn	string	Yes	Fiat token symbol, use symbol returned by /v1/tokens
amountIn	string	Yes	Input amount (smallest unit). After BufferPool quote conversion, must be ≥ 5 USDC
withdrawAddress	string	No	User-specified withdrawal address for onramp
chainId	string	No	Source chain ID, e.g. eip155:5000 (currently Mantle only)
dstChainId	string	No	Destination chain ID for bridge/swap, e.g. eip155:8453
dstAggregator	string	No	Aggregator contract address, use best.aggregator from quote
dstTokenOut	string	No	Destination token symbol
dstSwapCalldata	string	No	Swap calldata, use best.swapCalldata from quote
dstMinAmountOut	string	No	Minimum acceptable USDC amount (smallest unit), use best.minUsdcAmount from quote

Response Example

{
  "code": 0,
  "message": "",
  "data": {
    "txHash": "0x1234567890abcdef..."
  }
}

Description

• Returns txHash on success, transaction details can be queried via /v1/transactions.

• dstAggregator, dstSwapCalldata, dstMinAmountOut should come from the latest /v1/onramp/quote response.

• If no swap/bridge is needed, omit all dst* fields to perform only fiat token → USDC.

Fetch Onramp Quote

POST /v1/onramp/quote

Returns a real-time quote for fiat token → USDC (with optional swap/bridge info) based on BufferPool and limit rules.

Request Parameters

{
  "urId": 7639951412,
  "chainId": "eip155:5000",
  "fromToken": "USD",
  "toToken": "USDC",
  "amount": "10000",
  "slippageBps": 50
}

Field	Type	Required	Description
urId	int64	Yes	UR user ID
fromToken	string	Yes	Fiat token symbol, use symbol returned by /v1/tokens
toToken	string	Yes	Destination token symbol, use symbol returned by /v1/tokens
amount	string	Yes	Input amount (smallest unit). After BufferPool quote conversion, must be ≥ 5 USDC
slippageBps	int32	No	Slippage in bps, default 50
chainId	string	No	Chain ID, e.g. eip155:5000 (currently Mantle only)

Response Example

{
  "code": 0,
  "message": "",
  "data": {
    "quoteId": "onramp_1700000000000000000",
    "chainId": "eip155:5000",
    "best": {
      "aggregator": "0xAggregatorAddress",
      "to": "0xAggregatorTarget",
      "swapCalldata": "0xabcdef...",
      "minUsdcAmount": "99500000",
      "expectedUsdcAmount": "99800000",
      "slippageBps": 50,
      "deadline": 1700000000,
      "priceImpact": "0.0012"
    },
    "allQuotes": [
      {
        "source": "aggregatorA",
        "expectedUsdcAmount": "99800000",
        "priceImpact": "0.0012"
      }
    ],
    "isSupport": true,
    "needLivenessCheck": false,
    "outputAmount": "99800000",
    "exchangeRate": "0.9995",
    "crossChainFee": "0",
    "feeAmountViaUsdc": "500000",
    "feeAmountViaNativeToken": "0",
    "maxAmounts": {
      "USD": "50000",
      "EUR": "46500"
    },
    "livenessCheckUrl": "https://example.com?token=xxx&partnerId=7639951412"
  }
}

Response Field Description

Field	Type	Description
quoteId	string	Quote ID
chainId	string	Chain ID
best	object	Best quote details, see OnrampBestQuote
allQuotes	array	Aggregator quotes list, see OnrampAltQuote
feeAmountViaUsdc	string	Fee amount denominated in USDC (smallest unit)
outputAmount	string	Final output amount (smallest unit)
exchangeRate	string	Effective exchange rate after fee deduction
crossChainFee	string	Cross-chain fee (smallest unit)
feeAmountViaNativeToken	string	Fee amount denominated in native token (smallest unit)
isSupport	bool	Whether the current UR ID is allowed to continue onramp (based on liveness status, region restrictions, USDC de-peg checks, etc.)
needLivenessCheck	bool	Facial verification trigger: Indicates whether the current transaction requires a biometric liveness check (for example, a facial scan) before processing. This is dynamically determined by UR's risk engine based on the user's profile and requested onramp amount. If true, the frontend must guide the user through the verification flow.
maxAmounts	object	The maximum allowable input value for a single transaction. Any input exceeding this threshold will result in a transaction failure. Important: This limit is enforced strictly by risk control rules and is independent of the user's available monthly limit. Users may have sufficient monthly allowance but still be restricted by this single-transaction cap due to security policies.
livenessCheckUrl	string	Liveness check URL (only when isSupport && needLivenessCheck)

OnrampBestQuote

Field	Type	Description
aggregator	string	Aggregator name/address
to	string	Target contract address
swapCalldata	string	Swap calldata
minUsdcAmount	string	Minimum USDC output amount (smallest unit)
expectedUsdcAmount	string	Expected USDC output amount (smallest unit)
slippageBps	int32	Slippage in bps
deadline	int64	Quote deadline timestamp
priceImpact	string	Price impact

OnrampAltQuote

Field	Type	Description
source	string	Aggregator source
expectedUsdcAmount	string	Expected USDC output amount (smallest unit)
priceImpact	string	Price impact

Note: If isSupport = false, guide the user to try again later or complete the required liveness verification.

Fetch Transaction Details

Refers to this open API.

Webhooks

Webhook definitions are centralized in Webhooks. For delegated contract mode, the relevant events are transaction and allowance.

Environment

# sepolia
url: 

# auth sepolia
https://ur-fe-tob.qa4.gomantle.org/auth/authorize?state=1&partner_id={partner_id}&redirect_uri={redirect_uri}&response_type=code&scope=allowance.mantle.USDC%20allowance.mantle.USD24%20allowance.mantle.EUR24

# card url
https://ur-fe-tob.qa4.gomantle.org/partner-login?partnerId=90001&feature=card

# mainnet
url: https://openapi.ur.app

# auth 
https://get.ur.app/auth/authorize?state=1&partner_id={partner_id}&redirect_uri={redirect_uri}&response_type=code&scope=allowance.mantle.USDC%20allowance.mantle.USD24%20allowance.mantle.EUR24

# card url
https://get.ur.app/partner-login?partnerId={partnerId}&feature=card

Partner Configuration Required

signerAddress: Partner signing publicAddress
webhookUrl: URL to receive Webhook notifications
url: Web redirect URL (partner page linked from UR authorization page)
redirectDomain: Allowed auth redirect domains, multiple values supported for testing

Additional notes:

• Both environments have identical signature/authentication logic, differences only in on-chain data and chain ID, choose Base URL as needed.

• For QA, staging, or dedicated environments, please contact UR representative to obtain independent domain and public key.

Frequently Asked Questions (FAQ)

Authorization Flow Related

Q: How long is the authorization code valid?

A: Authorization codes are valid for 5 minutes by default and are single-use. Partners should call /v1/profile immediately after receiving the code to exchange for user information.

Q: What happens if the user denies authorization?

A: UR will redirect back to redirect_uri with an error parameter:

https://partner.com/callback?error=access_denied&error_description=User+denied+authorization&state=xxx

Q: Must redirect_uri be pre-registered?

A: Yes. For security, partners must pre-register all possible redirect_uri URLs in the UR system. During authorization, UR will verify if the redirect_uri in the URL is on the whitelist.

---

Error Code Description

Error Code	Description	Solution
10001	Invalid request signature (ErrSignatureInvalid)	Check signature algorithm, deadline, and whether private key is correct
20001	Request body is empty or missing required fields (ErrReqBodyEmpty)	Ensure request body is valid JSON and includes required fields
20002	Request body parsing failed (ErrParseRequestFailed)	Check JSON format, encoding, and Content-Type
20003	Invalid parameter (ErrInvalidParam), common in amount format, token name, urId errors	Adjust parameters based on error message, follow smallest unit string requirements
30001	NFT already exists (ErrNFTIdExists)	NFT already exists in DB or on-chain, use existing Token ID
50001	Server failed to read request (ErrIoRead)	Typically network read/write exception, can retry
50002	Internal error (ErrInternal)	UR internal service exception, retry later or contact UR support
50003	On-chain or external service exception (ErrChainRpc)	Chain RPC or third-party service failure, can retry later