> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lead.bank/llms.txt
> Use this file to discover all available pages before exploring further.

# Validations

> Best practices to reduce instant payment validation exceptions.

Lead does not queue instant payments. Instead, synchronous validation failures result in no creation of an `instant_payment` object and an HTTP error response, and asynchronous validation failures result in a `.rejected` webhook and a populated `rejection` hash with additional details. The table below contains a list of validations that Lead performs. We run validations synchronously and asynchronously.

| Lead Validation                         | Best Practice                                                                                                                                                             | Direction             |
| --------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------- |
| `parameters_invalid`                    | Ensure all request parameters are provided and adhere to Lead's rules.                                                                                                    | Outgoing              |
| `non_sufficient_funds`                  | Check if there are sufficient funds before requesting an outgoing payment.                                                                                                | Outgoing              |
| `account_number_incorrect`              | Check if the sender's account is active before attempting to send an outgoing payment.                                                                                    | Outgoing              |
| `limit_exceeded`                        | Request outgoing daily and 30-day payment limits that are consistent with the payment demand you expect. As your business grows, request that Lead increases your limits. | Outgoing              |
| `routing_number_format_incorrect`       | Check if the creditor's routing number is accurate before submitting an instant payment.                                                                                  | Outgoing              |
| `restricted_by_account_number_controls` | Use account number controls to constraint payment activity within known bounds. Ensure valid payments are not blocked by these restrictions.                              | Outgoing and incoming |
| `participant_not_on_network`            | Call the `/check_availability` endpoint to verify that a creditor is enabled for instant payments before creating an outgoing instant payment.                            | Outgoing              |
| `participant_signed_off`                | This may occur if a counterparty is offline during maintenance or downtime. There is nothing you can do to avoid this error.                                              | Outgoing              |
| `creditor_name_mismatch`                | Ensure your customers and the parties they transact with are aware that creditor names must be accurate.                                                                  | Incoming              |