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

# Create Preauth Signals

export const ParamList = ({items = [], is_child = false}) => {
  return items.map(item => {
    const field_props = {
      id: Math.random().toString(),
      body: item.name,
      name: item.name,
      type: item.type,
      required: item.required
    };
    const enums = item.enums || [];
    const items = item.items || [];
    const has_items = items?.length > 0;
    const has_enums = enums?.length > 0;
    const should_default_open = item.defaultOpen || false;
    const render_child_item = () => {
      const child_props = {
        title: has_enums ? "Possible enum values" : "properties"
      };
      if (should_default_open) child_props.defaultOpen = true;
      const has_inline_enums = has_enums && enums.every(enum_item => typeof enum_item === 'string') && enums.map((enum_item, idx) => {
        const is_last = idx === enums.length - 1;
        const is_2nd_to_last = idx === enums.length - 2;
        return <>
            <code>{enum_item}</code>
            {is_last && ''}
            {is_2nd_to_last && ' or '}
            {!is_last && !is_2nd_to_last && ', '}
          </>;
      });
      const enum_list = has_enums && !has_inline_enums && <Accordion {...child_props}>
          {enums.map((enum_item, index) => <div key={`enum-${index}`}>
              <code>{enum_item.name}</code>
              <br />
              <p>{enum_item.description}</p>
            </div>)}
        </Accordion>;
      const item_list = has_items && <Expandable {...child_props}>
          <ParamList items={items || []} is_child />
        </Expandable>;
      return <>
          <p>
            {item.description}
            {has_inline_enums && [has_inline_enums.length > 1 ? ' One of ' : ' Must be ', ...has_inline_enums]}
          </p>

          {enum_list}
          {item_list}
        </>;
    };
    return is_child ? <ResponseField {...field_props}>{render_child_item()}</ResponseField> : <ParamField {...field_props}>{render_child_item()}</ParamField>;
  });
};

Computes a PreauthSignals assessment for a connected credit card Account.

Operation Type: <Tooltip tip="Your request is processed immediately, and you'll receive a response before proceeding.">⚡ Synchronous</Tooltip>

## Path Parameters

<ParamList
  items={[
{
name: 'acc_id',
type: 'string',
required: true,
description: 'The ID of a liability-backed credit card Account.',
},
]}
/>

## Body

<ParamList
  items={[
{
name: 'purchase', type: 'object', required: true,
description: 'The transaction being assessed.',
items: [
  { name: 'purchase.amount', type: 'integer', required: true, description: 'Charge amount in cents. Must be at least 1.' },
  { name: 'purchase.mcc', type: 'string', required: false, description: 'Merchant category code.' },
  { name: 'purchase.ip_address', type: 'string', required: false, description: 'Cardholder IP address at checkout.' },
  { name: 'purchase.txn_time', type: 'string', required: false, description: 'ISO 8601 timestamp of intended charge. Defaults to request time.' }
]
},
{ name: 'metadata', type: 'object | null', required: false, description: 'Additional data to attach to the assessment.' }
]}
/>

## Returns

Returns a PreauthSignals object.

<br />

<RequestExample>
  ```bash cURL theme={null}
  curl https://production.methodfi.com/accounts/acc_4m9amk4KFiaQX/preauth \
    -X POST \
    -H "Method-Version: 2026-03-30" \
    -H "Authorization: Bearer sk_WyZEWVfTcH7GqmPzUPk65Vjc" \
    -H "Content-Type: application/json" \
    -d '{
      "purchase": {
        "amount": 9999,
        "mcc": "4511",
        "ip_address": "203.0.113.42",
        "txn_time": "2026-05-28T14:00:00Z"
      }
    }'
  ```
</RequestExample>

<ResponseExample>
  ```json theme={null}
  {
    "id": "preauth_qV7kRaFm4JNxw",
    "account_id": "acc_4m9amk4KFiaQX",
    "status": "completed",
    "verified_ownership": "match",
    "card_standing": "active",
    "success_likelihood": 0.82,
    "optimal_retry_date": "2026-05-28",
    "error": null,
    "metadata": null,
    "created_at": "2026-05-28T14:00:00.000Z",
    "updated_at": "2026-05-28T14:00:00.180Z"
  }
  ```
</ResponseExample>

## Errors

* An unknown `acc_id` returns `404`.
* An Account that is not a liability-backed credit card returns `400` with `PREAUTH_ACCOUNT_NOT_SUPPORTED`.
* An Account with withdrawn consent returns `400` with `PREAUTH_ACCOUNT_CONSENT_WITHDRAWN`.
* A disabled Account returns `400` with `PREAUTH_ACCOUNT_DISABLED`.
* If the Account's underlying liability cannot be found while processing a valid request, the assessment returns `status: "failed"` with `error.sub_type: "PREAUTH_FAILED_LIABILITY_NOT_FOUND"`.


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.