> ## Documentation Index > Fetch the complete documentation index at: https://docs.lightspark.com/llms.txt > Use this file to discover all available pages before exploring further. # Look up an UMA address for payment > Lookup a receiving UMA address to determine supported currencies and exchange rates. This endpoint helps platforms determine what currencies they can send to a given UMA address. ## OpenAPI ````yaml https://app.stainless.com/api/spec/documented/grid/openapi.documented.yml get /receiver/uma/{receiverUmaAddress} openapi: 3.1.0 info: title: Grid API description: > API for managing global payments on the open Money Grid. Built by Lightspark. See the full documentation at https://docs.lightspark.com/. version: '2025-10-13' contact: name: Lightspark Support email: support@lightspark.com license: name: Proprietary url: https://lightspark.com/terms servers: - url: https://api.lightspark.com/grid/2025-10-13 description: Production server security: - BasicAuth: [] - AgentAuth: [] tags: - name: Platform Configuration description: >- Platform configuration endpoints for managing global settings. You can also configure these settings in the Grid dashboard. - name: Customers description: >- Customer management endpoints for creating and updating customer information - name: KYC/KYB Verifications description: >- Endpoints for Know Your Customer (KYC) and Know Your Business (KYB) verification, including managing beneficial owners and triggering verification for customers. - name: Documents description: >- Endpoints for uploading and managing verification documents for customers and beneficial owners. Supports KYC and KYB document requirements. - name: Internal Accounts description: >- Internal account management endpoints for creating and managing internal accounts - name: External Accounts description: >- External account management endpoints for creating and managing external bank accounts - name: Same-Currency Transfers description: >- Endpoints for transferring funds between internal and external accounts with the same currency - name: Cross-Currency Transfers description: Endpoints for creating and confirming quotes for cross-currency transfers - name: Transactions description: Endpoints for retrieving transaction information - name: Webhooks description: Webhook endpoints and configuration for receiving notifications - name: Invitations description: Endpoints for creating, claiming and managing UMA invitations - name: Sandbox description: Endpoints to trigger test cases in sandbox - name: API Tokens description: Endpoints to programmatically manage API tokens - name: Exchange Rates description: >- Endpoints for retrieving cached foreign exchange rates. Rates are cached for approximately 5 minutes and include platform-specific fees. - name: Discoveries description: >- Endpoints for discovering available payment rails, banks, and providers for a given country and currency corridor. - name: Embedded Wallet Auth description: >- Endpoints for registering and verifying end-user authentication credentials (email OTP, OAuth, passkey) used to sign Embedded Wallet actions. - name: Agent Management description: >- Endpoints for creating and managing agents (experimental), called by the partner's backend using platform credentials. Covers the full agent lifecycle: creation, policy configuration, pausing, deletion, the device code installation flow, and approving or rejecting transactions initiated by agents. - name: Agent Operations description: >- Endpoints called by the agent itself using its own credentials (obtained via device code redemption). Scoped to the agent's associated customer — all requests automatically operate on behalf of that customer and are subject to the agent's policy. When an action requires approval, the resulting transaction enters a pending state and must be approved by the platform via `POST /transactions/{transactionId}/approve`. - name: Cards description: >- Card management endpoints. Issue debit cards against an internal account, freeze / unfreeze, close, manage card funding sources, and list card transactions. paths: /receiver/uma/{receiverUmaAddress}: get: tags: - Cross-Currency Transfers summary: Look up an UMA address for payment description: > Lookup a receiving UMA address to determine supported currencies and exchange rates. This endpoint helps platforms determine what currencies they can send to a given UMA address. operationId: lookupUma parameters: - name: receiverUmaAddress in: path description: UMA address of the intended recipient required: true schema: type: string - name: senderUmaAddress in: query description: UMA address of the sender (optional if customerId is provided) required: false schema: type: string - name: customerId in: query description: System ID of the sender (optional if senderUmaAddress is provided) required: false schema: type: string responses: '200': description: Successful lookup content: application/json: schema: $ref: '#/components/schemas/ReceiverUmaLookupResponse' '400': description: Bad request - Missing or invalid parameters content: application/json: schema: $ref: '#/components/schemas/Error400' '401': description: Unauthorized content: application/json: schema: $ref: '#/components/schemas/Error401' '404': description: >- UMA address not found. The address is well-formed but no receiver exists at the counterparty VASP (`UMA_NOT_FOUND`). content: application/json: schema: $ref: '#/components/schemas/Error404' '412': description: Counterparty doesn't support UMA version content: application/json: schema: $ref: '#/components/schemas/Error412' '424': description: Counterparty issue content: application/json: schema: $ref: '#/components/schemas/Error424' '500': description: Internal service error content: application/json: schema: $ref: '#/components/schemas/Error500' security: - BasicAuth: [] x-codeSamples: - lang: JavaScript source: >- import LightsparkGrid from '@lightsparkdev/grid'; const client = new LightsparkGrid({ username: process.env['GRID_CLIENT_ID'], // This is the default and can be omitted password: process.env['GRID_CLIENT_SECRET'], // This is the default and can be omitted }); const umaLookupResponse = await client.receiver.lookupUma('receiverUmaAddress'); console.log(umaLookupResponse); - lang: Python source: |- import os from grid import LightsparkGrid client = LightsparkGrid( username=os.environ.get("GRID_CLIENT_ID"), # This is the default and can be omitted password=os.environ.get("GRID_CLIENT_SECRET"), # This is the default and can be omitted ) uma_lookup_response = client.receiver.lookup_uma( receiver_uma_address="receiverUmaAddress", ) print(uma_lookup_response) - lang: Go source: "package main\n\nimport (\n\t\"context\"\n\t\"fmt\"\n\n\t\"github.com/stainless-sdks/grid-go\"\n\t\"github.com/stainless-sdks/grid-go/option\"\n)\n\nfunc main() {\n\tclient := grid.NewClient(\n\t\toption.WithUsername(\"My Username\"),\n\t\toption.WithPassword(\"My Password\"),\n\t)\n\tumaLookupResponse, err := client.Receiver.LookupUma(\n\t\tcontext.TODO(),\n\t\t\"receiverUmaAddress\",\n\t\tgrid.ReceiverLookupUmaParams{},\n\t)\n\tif err != nil {\n\t\tpanic(err.Error())\n\t}\n\tfmt.Printf(\"%+v\\n\", umaLookupResponse)\n}\n" - lang: Kotlin source: |- package com.lightspark.grid.example import com.lightspark.grid.client.LightsparkGridClient import com.lightspark.grid.client.okhttp.LightsparkGridOkHttpClient import com.lightspark.grid.models.receiver.ReceiverLookupUmaParams import com.lightspark.grid.models.receiver.UmaLookupResponse fun main() { val client: LightsparkGridClient = LightsparkGridOkHttpClient.fromEnv() val umaLookupResponse: UmaLookupResponse = client.receiver().lookupUma("receiverUmaAddress") } - lang: Ruby source: >- require "grid" lightspark_grid = Grid::Client.new(username: "My Username", password: "My Password") uma_lookup_response = lightspark_grid.receiver.lookup_uma("receiverUmaAddress") puts(uma_lookup_response) - lang: PHP source: |- receiver->lookupUma( 'receiverUmaAddress', customerID: 'customerId', senderUmaAddress: 'senderUmaAddress', ); var_dump($umaLookupResponse); } catch (APIException $e) { echo $e->getMessage(); } - lang: C# source: |- using System; using Grid; using Grid.Models.Receiver; LightsparkGridClient client = new(); ReceiverLookupUmaParams parameters = new() { ReceiverUmaAddress = "receiverUmaAddress" }; var umaLookupResponse = await client.Receiver.LookupUma(parameters); Console.WriteLine(umaLookupResponse); - lang: CLI source: |- grid receiver lookup-uma \ --username 'My Username' \ --password 'My Password' \ --receiver-uma-address receiverUmaAddress components: schemas: ReceiverUmaLookupResponse: allOf: - $ref: '#/components/schemas/ReceiverLookupResponse' - type: object required: - receiverUmaAddress properties: receiverUmaAddress: type: string description: The UMA address that was looked up example: $receiver@uma.domain Error400: type: object required: - message - status - code properties: status: type: integer enum: - 400 description: HTTP status code code: type: string description: > | Error Code | Description | |------------|-------------| | INVALID_INPUT | Invalid input provided | | MISSING_MANDATORY_USER_INFO | Required customer information is missing | | INVITATION_ALREADY_CLAIMED | Invitation has already been claimed | | INVITATIONS_NOT_CONFIGURED | Invitations are not configured | | INVALID_UMA_ADDRESS | UMA address format is invalid | | INVITATION_CANCELLED | Invitation has been cancelled | | QUOTE_REQUEST_FAILED | An issue occurred during the quote process; this is retryable | | INVALID_PAYREQ_RESPONSE | Counterparty Payreq response was invalid | | INVALID_RECEIVER | Receiver is invalid | | PARSE_PAYREQ_RESPONSE_ERROR | Error parsing receiver PayReq response | | CERT_CHAIN_INVALID | Counterparty certificate chain is invalid | | CERT_CHAIN_EXPIRED | Counterparty certificate chain has expired | | INVALID_PUBKEY_FORMAT | Counterparty Public key format is invalid | | MISSING_REQUIRED_UMA_PARAMETERS | Counterparty required UMA parameters are missing | | SENDER_NOT_ACCEPTED | Sender is not accepted | | AMOUNT_OUT_OF_RANGE | Amount is out of range | | INVALID_CURRENCY | Currency is invalid | | INVALID_TIMESTAMP | Timestamp is invalid | | INVALID_NONCE | Nonce is invalid | | INVALID_REQUEST_FORMAT | Request format is invalid | | INVALID_BANK_ACCOUNT | Bank account is invalid | | SELF_PAYMENT | Self payment not allowed | | LOOKUP_REQUEST_FAILED | Lookup request failed | | PARSE_LNURLP_RESPONSE_ERROR | Error parsing LNURLP response | | INVALID_AMOUNT | Amount is invalid | | WEBHOOK_ENDPOINT_NOT_SET | Webhook endpoint is not set | | WEBHOOK_DELIVERY_ERROR | Webhook delivery error | | LOW_QUALITY | Document quality too low to process | | DATA_MISMATCH | Document details don't match provided information | | EXPIRED | Document has expired | | SUSPECTED_FRAUD | Document suspected of being forged or edited | | UNSUITABLE_DOCUMENT | Document type is not accepted or not supported | | INCOMPLETE | Document is missing pages or sides | | EMAIL_OTP_CREDENTIAL_ALREADY_EXISTS | An EMAIL_OTP credential is already registered on the target internal account; only one email OTP credential is supported per internal account at this time | | PASSKEY_CREDENTIAL_ALREADY_EXISTS | A PASSKEY credential with the same WebAuthn credentialId is already registered on the target internal account | enum: - INVALID_INPUT - MISSING_MANDATORY_USER_INFO - INVITATION_ALREADY_CLAIMED - INVITATIONS_NOT_CONFIGURED - INVALID_UMA_ADDRESS - INVITATION_CANCELLED - QUOTE_REQUEST_FAILED - INVALID_PAYREQ_RESPONSE - INVALID_RECEIVER - PARSE_PAYREQ_RESPONSE_ERROR - CERT_CHAIN_INVALID - CERT_CHAIN_EXPIRED - INVALID_PUBKEY_FORMAT - MISSING_REQUIRED_UMA_PARAMETERS - SENDER_NOT_ACCEPTED - AMOUNT_OUT_OF_RANGE - INVALID_CURRENCY - INVALID_TIMESTAMP - INVALID_NONCE - INVALID_REQUEST_FORMAT - INVALID_BANK_ACCOUNT - SELF_PAYMENT - LOOKUP_REQUEST_FAILED - PARSE_LNURLP_RESPONSE_ERROR - INVALID_AMOUNT - WEBHOOK_ENDPOINT_NOT_SET - WEBHOOK_DELIVERY_ERROR - LOW_QUALITY - DATA_MISMATCH - EXPIRED - SUSPECTED_FRAUD - UNSUITABLE_DOCUMENT - INCOMPLETE - EMAIL_OTP_CREDENTIAL_ALREADY_EXISTS - PASSKEY_CREDENTIAL_ALREADY_EXISTS message: type: string description: Error message details: type: object description: Additional error details additionalProperties: true Error401: type: object required: - message - status - code properties: status: type: integer enum: - 401 description: HTTP status code code: type: string description: > | Error Code | Description | |------------|-------------| | UNAUTHORIZED | Issue with API credentials | | INVALID_SIGNATURE | Signature header is invalid | | WALLET_SIGNATURE_MISSING | The `Grid-Wallet-Signature` header is required for this Embedded Wallet action but was not supplied | | WALLET_SIGNATURE_MALFORMED | The `Grid-Wallet-Signature` header could not be parsed (bad encoding, structure, or fields) | | WALLET_SIGNATURE_BODY_MISMATCH | The `Grid-Wallet-Signature` was computed over a different request body than the one received | | WALLET_SIGNATURE_INVALID | The `Grid-Wallet-Signature` failed cryptographic verification against the registered credential | | REQUEST_ID_MISSING | The `Request-Id` header is required on the signed retry but was not supplied (paired with `Grid-Wallet-Signature`) | enum: - UNAUTHORIZED - INVALID_SIGNATURE - WALLET_SIGNATURE_MISSING - WALLET_SIGNATURE_MALFORMED - WALLET_SIGNATURE_BODY_MISMATCH - WALLET_SIGNATURE_INVALID - REQUEST_ID_MISSING message: type: string description: Error message details: type: object description: Additional error details additionalProperties: true Error404: type: object required: - message - status - code properties: status: type: integer enum: - 404 description: HTTP status code code: type: string description: > | Error Code | Description | |------------|-------------| | TRANSACTION_NOT_FOUND | Transaction not found | | INVITATION_NOT_FOUND | Invitation not found | | USER_NOT_FOUND | Customer not found | | QUOTE_NOT_FOUND | Quote not found | | LOOKUP_REQUEST_NOT_FOUND | Lookup request not found | | TOKEN_NOT_FOUND | Token not found | | BULK_UPLOAD_JOB_NOT_FOUND | Bulk upload job not found | | REFERENCE_NOT_FOUND | Reference not found | | UMA_NOT_FOUND | The UMA address is well-formed but no receiver exists at the counterparty VASP | enum: - TRANSACTION_NOT_FOUND - INVITATION_NOT_FOUND - USER_NOT_FOUND - QUOTE_NOT_FOUND - LOOKUP_REQUEST_NOT_FOUND - TOKEN_NOT_FOUND - BULK_UPLOAD_JOB_NOT_FOUND - REFERENCE_NOT_FOUND - UMA_NOT_FOUND message: type: string description: Error message details: type: object description: Additional error details additionalProperties: true Error412: type: object required: - message - status - code properties: status: type: integer enum: - 412 description: HTTP status code code: type: string description: > | Error Code | Description | |------------|-------------| | UNSUPPORTED_UMA_VERSION | Counterparty doesn't support the Grid UMA version | enum: - UNSUPPORTED_UMA_VERSION message: type: string description: Error message details: type: object description: Additional error details additionalProperties: true Error424: type: object required: - message - status - code properties: status: type: integer enum: - 424 description: HTTP status code code: type: string description: > | Error Code | Description | |------------|-------------| | PAYREQ_REQUEST_FAILED | Payment request failed | | COUNTERPARTY_PUBKEY_FETCH_ERROR | Error fetching counterparty public key | | NO_COMPATIBLE_UMA_VERSION | No compatible UMA version | | LNURLP_REQUEST_FAILED | LNURLP request failed | | EMAIL_OTP_CREDENTIAL_SYNC_FAILED | Failed to update one or more tied EMAIL_OTP credentials | enum: - PAYREQ_REQUEST_FAILED - COUNTERPARTY_PUBKEY_FETCH_ERROR - NO_COMPATIBLE_UMA_VERSION - LNURLP_REQUEST_FAILED - EMAIL_OTP_CREDENTIAL_SYNC_FAILED message: type: string description: Error message details: type: object description: Additional error details additionalProperties: true Error500: type: object required: - message - status - code properties: status: type: integer enum: - 500 description: HTTP status code code: type: string description: | | Error Code | Description | |------------|-------------| | GRID_SWITCH_ERROR | Grid switch error | | INTERNAL_ERROR | Internal server or UMA error | enum: - GRID_SWITCH_ERROR - INTERNAL_ERROR message: type: string description: Error message details: type: object description: Additional error details additionalProperties: true ReceiverLookupResponse: type: object required: - supportedCurrencies - lookupId properties: supportedCurrencies: type: array description: List of currencies supported by the receiving account items: $ref: '#/components/schemas/CurrencyPreference' requiredPayerDataFields: type: array description: >- Fields required by the receiving institution about the payer before payment can be completed items: $ref: '#/components/schemas/CounterpartyFieldDefinition' lookupId: type: string description: >- Unique identifier for the lookup. Needed in the subsequent create quote request. example: Lookup:019542f5-b3e7-1d02-0000-000000000009 CurrencyPreference: type: object required: - currency - estimatedExchangeRate - min - max properties: currency: $ref: '#/components/schemas/Currency' estimatedExchangeRate: type: number description: >- An estimated exchange rate from the sender's currency to this currency. This is not a locked rate and is subject to change when calling the quotes endpoint. exclusiveMinimum: 0 example: 1.08 min: type: integer format: int64 description: The minimum amount that can be received in this currency. exclusiveMinimum: 0 example: 1 max: type: integer format: int64 description: The maximum amount that can be received in this currency. exclusiveMinimum: 0 example: 1000000 CounterpartyFieldDefinition: type: object properties: name: $ref: '#/components/schemas/CustomerInfoFieldName' mandatory: type: boolean description: Whether the field is mandatory example: true required: - name - mandatory Currency: type: object properties: code: type: string description: >- Three-letter currency code (ISO 4217) for fiat currencies. Some cryptocurrencies may use their own ticker symbols (e.g. "BTC" for Bitcoin, "USDC" for USDC, etc.) example: USD name: type: string description: Full name of the currency example: United States Dollar symbol: type: string description: Symbol of the currency example: $ decimals: type: integer description: Number of decimal places for the currency minimum: 0 example: 2 CustomerInfoFieldName: type: string enum: - FULL_NAME - BIRTH_DATE - NATIONALITY - PHONE_NUMBER - EMAIL - POSTAL_ADDRESS - TAX_ID - REGISTRATION_NUMBER - USER_TYPE - COUNTRY_OF_RESIDENCE - ACCOUNT_IDENTIFIER - FI_LEGAL_ENTITY_NAME - FI_ADDRESS - PURPOSE_OF_PAYMENT - ULTIMATE_INSTITUTION_COUNTRY - IDENTIFIER - BUSINESS_TYPE - COMPANY_LEGAL_NAME - ID_TYPE - ID_NUMBER description: >- Name of a type of field containing info about a platform's customer or counterparty customer. example: FULL_NAME securitySchemes: BasicAuth: type: http scheme: basic description: >- API token authentication using format `:` AgentAuth: type: http scheme: bearer description: >- Bearer token authentication for agent-scoped endpoints. The token is the `accessToken` returned when redeeming a device code via `POST /agents/device-codes/{code}/redeem`. Agent credentials are user-scoped: all requests are automatically bound to the agent's associated customer and subject to the agent's policy. ````