> ## Documentation Index > Fetch the complete documentation index at: https://partner-help.letsdothis.com/llms.txt > Use this file to discover all available pages before exploring further. # Check whether an email is registered > Answers whether an email address holds a confirmed place in the event occurrence. Built for partners who need a yes/no at the point of sale — a sponsor validating a participant discount, for example — without access to any participant data. The response carries only the occurrence id and the answer, and an email that is not registered (or has never been seen) is simply `false`. Only entries with a confirmed status count. Pending payment, deferred, withdrawn, cancelled, refunded and transferred entries answer `false`. Send the email in the request body, not the URL. Matching is case-insensitive and ignores surrounding whitespace. Supports [scoped API keys](/api-reference/scoped-keys): this is the `registrationStatus` endpoint, and it reads the occurrence from the path. A key limited by endpoint must include `registrationStatus`; a key limited by occurrence must include the occurrence in the path; a key limited by both must satisfy both. This endpoint is rate limited per API key in two ways: a burst limit of a few requests per second, and a daily quota that bounds what one key can look up in 24 hours. Exceeding either answers `429`; the burst limit includes a `retry-after` header. ## OpenAPI ````yaml /openapi.json post /v0/event-occurrences/{id}/registration-status openapi: 3.1.0 info: title: Let's Do This API version: 0.1.0 description: > The full reference — getting started, pagination, error responses, rate limits and the changelog — lives at [partner-help.letsdothis.com/api-reference](https://partner-help.letsdothis.com/api-reference/overview). This page is the interactive OpenAPI view of the same specification. # Authentication Create an API key from **Settings** → **Credentials** in your Let's Do This account and send it as a bearer token: ```bash curl --request GET \ --url "https://api.letsdothis.com/v0/participants" \ --header "Authorization: Bearer YOUR-API-KEY" ``` Keep the key secret: it identifies your organization, so do not ship it in a website or native app. If a key is exposed, revoke it from the same section and create a replacement. # OpenAPI schema Download the [OpenAPI schema](https://api.letsdothis.com/documentation/json) to use with Postman or an OpenAPI client generator. servers: - url: https://api.letsdothis.com description: Production - url: https://api.staging.letsdothis.com description: Staging security: - bearerAuth: [] tags: - name: Events x-group: Events description: Events that participants can register for. - name: EventOccurrences x-group: Event occurrences description: >- Event occurrences scoped to the organizer associated with your Public API credentials. Unlike the public Events catalog, results are limited to your own events. - name: Races x-group: Races description: >- Races within an event occurrence. An event occurrence may have one or more races, for example a 5K and a 10K within the same race day. - name: Tickets x-group: Tickets description: Tickets that are available for events. - name: BookingForms x-group: Booking forms description: >- Booking forms define the questions a booker answers when registering for a ticket. A ticket usually references a single booking form, so expect zero or one, while a booking form may be shared across multiple tickets. - name: BookingFormFields x-group: Booking form fields description: >- Booking form fields are the individual questions on a booking form — their type, label, options, and whether an answer is required. A field can be reused across multiple forms. - name: Bookings x-group: Bookings description: >- Bookings are the transaction record for a registration. A booking may contain one or more participants (entries). - name: Participant x-group: Participants description: Participants are users who successfully booked an event. - name: LineItem x-group: Line items description: Financial details related to individual items within transactions. - name: AddOns x-group: Add-ons description: >- Organizer-owned products that can be purchased and allocated to participants. Imported products retain stable external identities. - name: DiscountCodes x-group: Discount codes description: >- Discount codes participants enter at checkout to reduce the price of a booking. - name: Credits x-group: Credits description: >- Credits are balances participants can spend at checkout, identified by their email address. - name: Referrals x-group: Referrals description: >- Referral programs, the referrers registered on them, and asynchronous imports of historical referrals. - name: Application x-group: Applications description: >- Applications are created when a user applies for tickets that are set up to require an application process, such as balloted or "Good For Age" entries. - name: Partner x-group: Partners description: >- Partners that were created by the organization who can have Reserved Entries assigned to them. - name: ReservedEntries x-group: Reserved entries description: >- Reserved Entries are entries that are reserved for a partner. After being assigned, the partner can then allocate these entries to participants. - name: Timing x-group: Timing description: >- Timing providers push bib numbers and bib-pack shipments back to Let's Do This for the startlist entries they received. Available to select timing partners only. paths: /v0/event-occurrences/{id}/registration-status: post: tags: - EventOccurrences summary: Check whether an email is registered description: >- Answers whether an email address holds a confirmed place in the event occurrence. Built for partners who need a yes/no at the point of sale — a sponsor validating a participant discount, for example — without access to any participant data. The response carries only the occurrence id and the answer, and an email that is not registered (or has never been seen) is simply `false`. Only entries with a confirmed status count. Pending payment, deferred, withdrawn, cancelled, refunded and transferred entries answer `false`. Send the email in the request body, not the URL. Matching is case-insensitive and ignores surrounding whitespace. Supports [scoped API keys](/api-reference/scoped-keys): this is the `registrationStatus` endpoint, and it reads the occurrence from the path. A key limited by endpoint must include `registrationStatus`; a key limited by occurrence must include the occurrence in the path; a key limited by both must satisfy both. This endpoint is rate limited per API key in two ways: a burst limit of a few requests per second, and a daily quota that bounds what one key can look up in 24 hours. Exceeding either answers `429`; the burst limit includes a `retry-after` header. parameters: - schema: type: string example: '12345678901' in: path name: id required: true description: The ID of the event occurrence to query by. requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/RegistrationStatusRequest' responses: '200': description: Default Response content: application/json: schema: $ref: '#/components/schemas/RegistrationStatus' '400': description: Bad request content: application/json: schema: description: Bad request type: object properties: statusCode: type: number enum: - 400 error: type: string message: type: string '401': description: Unauthorized content: application/json: schema: description: Unauthorized type: object properties: statusCode: type: number enum: - 401 error: type: string message: type: string '403': description: Forbidden content: application/json: schema: description: Forbidden type: object properties: statusCode: type: number enum: - 403 error: type: string message: type: string '404': description: Not found content: application/json: schema: description: Not found type: object properties: statusCode: type: number enum: - 404 error: type: string message: type: string '429': description: Rate limit exceeded headers: retry-after: schema: type: integer description: Seconds to wait before retrying the request. x-ratelimit-limit: schema: type: integer description: Requests permitted in the current window. x-ratelimit-remaining: schema: type: integer description: Requests still permitted in the current window. x-ratelimit-reset: schema: type: integer description: Seconds until the current window resets. content: application/json: schema: description: Rate limit exceeded type: object properties: statusCode: type: number enum: - 429 error: type: string message: type: string components: schemas: RegistrationStatusRequest: title: RegistrationStatusRequest type: object properties: email: type: string description: >- The participant's email address as entered at registration. Matching is case-insensitive and ignores surrounding whitespace. format: email maxLength: 254 example: runner@example.com required: - email additionalProperties: false description: Ask whether an email address is registered for an event occurrence. example: email: runner@example.com RegistrationStatus: title: RegistrationStatus type: object properties: eventOccurrenceId: type: string description: The event occurrence the answer is for. example: '12345678901' registered: type: boolean description: >- `true` when the email holds at least one confirmed entry in the occurrence. Pending, deferred, withdrawn, cancelled, refunded and transferred entries do not count, and an email we have never seen is simply `false`. required: - eventOccurrenceId - registered additionalProperties: false description: >- Whether an email address holds a confirmed place in an event occurrence. Deliberately carries nothing about the participant beyond the answer. example: eventOccurrenceId: '12345678901' registered: true securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: JWT ````