---
title: "Begin discoverable passkey authentication"
method: POST
path: "/auth/passkeys/assert/options"
tags: ["Auth"]
---

# Begin discoverable passkey authentication

`POST /auth/passkeys/assert/options`

## Request

- Base URL: `https://api.medianfi.com/api/v1`
- URL: `https://api.medianfi.com/api/v1/auth/passkeys/assert/options`
- Auth: none required

Does not accept an email or other account identifier.

## Headers

- `X-Median-App-Surface` 'qa'

## Request body

- PasskeyAssertionOptionsInput
  - `recaptchaToken` string, required

## Response `200`

Browser assertion options and one-shot HttpOnly ceremony cookie

- PasskeyOptionsResponse
  - `success` true, required
  - `data` object, required
    - `options` object, required

## Other responses

- `400`: Request body is not valid JSON
- `401`: The credential or one-shot ceremony is invalid, expired, or already used
- `403`: reCAPTCHA verification is required, unavailable, or failed
- `404`: Onboarding v3 is disabled; the route is hidden
- `413`: Request body exceeds the passwordless route limit
- `415`: Request body charset or content encoding is unsupported
- `422`: Validation error
- `429`: Retry after the indicated number of seconds

---

[API](https://skmtc.dev/medianfi/apis/median-api.md) · [All operations](https://skmtc.dev/medianfi/apis/median-api/llms.txt) · [OpenAPI document](https://skmtc.dev/medianfi/apis/median-api/revisions/20090ea32b0d?raw)