> ## Documentation Index > Fetch the complete documentation index at: https://docs.kalshi.com/llms.txt > Use this file to discover all available pages before exploring further. # Create Concert Cancellation Market > Returns the on-request market on whether a concert is called off, creating it if it doesn't exist yet. A market is defined by the show (`jambase_event_id`), the date it is scheduled for and the `cover`: `postponed`, `cancelled` or `either`. The same request always returns the same market, so call this before sending an RFQ for a market you haven't seen. `created` tells you whether the market is new. Take `jambase_event_id` and `scheduled_date` from `GET /concert_cancellation_markets/concerts` or `GET /concert_cancellation_markets/concerts/search`. A new market is created from the show's listing as it stands now, so the request is refused when the show has moved to another date or has already been canceled or postponed. An existing market is returned until it closes, even when new markets are no longer offered. A new market's show must start more than an hour from now and within the `max_days_ahead` that `GET /concert_cancellation_markets/availability` reports. A market is traded through RFQs: pass the returned `market_ticker` to `POST /communications/rfqs`. These markets are in series starting with `KXRFQ` and are left out of unscoped market listings. A market created a moment ago may not be readable yet: if `GET /markets/{ticker}` returns 404 right after creation, retry. Errors carry the specific reason in `details`: | Status | `code` | When | | --- | --- | --- | | 400 | `bad_request` | The body isn't valid JSON, or a field has the wrong type. | | 400 | `missing_parameters` | A required field is missing or empty. | | 400 | `invalid_parameters` | A field is present but unusable: an unknown cover, a `jambase_event_id` that isn't `jambase:`, a `scheduled_date` that isn't YYYY-MM-DD, or a show scheduled further ahead than `max_days_ahead`. | | 404 | `not_found` | The listing source has no show with that id. | | 409 | `concert_cancellation_market_unavailable` | The request is valid but the market isn't offered: concert markets or the cover are switched off, the show is now listed on another date, has already been canceled or postponed, starts too soon, isn't a concert, or its market has closed. | | 429 | `concert_cancellation_market_limit_exceeded` | The daily limit on new concert markets across all users was reached. Retrying at once doesn't help. | | 429 | `too_many_requests` | Your API rate limit. This endpoint is charged against your write budget. | ## OpenAPI ````yaml /openapi.yaml post /concert_cancellation_markets openapi: 3.0.0 info: title: Kalshi Trade API Manual Endpoints version: 3.36.0 description: >- Manually defined OpenAPI spec for endpoints being migrated to spec-first approach servers: - url: https://external-api.kalshi.com/trade-api/v2 description: Production Trade API server - url: https://api.elections.kalshi.com/trade-api/v2 description: Production shared API server, also supported - url: https://external-api.demo.kalshi.co/trade-api/v2 description: Demo Trade API server - url: https://demo-api.kalshi.co/trade-api/v2 description: Demo shared API server, also supported security: [] tags: - name: api-keys description: API key management endpoints - name: orders description: Order management endpoints - name: order-groups description: Order group management endpoints - name: portfolio description: Portfolio and balance information endpoints - name: communications description: Request-for-quote (RFQ) endpoints - name: multivariate description: Multivariate event collection endpoints - name: exchange description: Exchange status and information endpoints - name: live-data description: Live data endpoints - name: markets description: Market data endpoints - name: milestone description: Milestone endpoints - name: search description: Search and filtering endpoints - name: incentive-programs description: Incentive program endpoints - name: fcm description: FCM member specific endpoints - name: events description: Event endpoints - name: structured-targets description: Structured targets endpoints paths: /concert_cancellation_markets: post: tags: - markets summary: Create Concert Cancellation Market description: > Returns the on-request market on whether a concert is called off, creating it if it doesn't exist yet. A market is defined by the show (`jambase_event_id`), the date it is scheduled for and the `cover`: `postponed`, `cancelled` or `either`. The same request always returns the same market, so call this before sending an RFQ for a market you haven't seen. `created` tells you whether the market is new. Take `jambase_event_id` and `scheduled_date` from `GET /concert_cancellation_markets/concerts` or `GET /concert_cancellation_markets/concerts/search`. A new market is created from the show's listing as it stands now, so the request is refused when the show has moved to another date or has already been canceled or postponed. An existing market is returned until it closes, even when new markets are no longer offered. A new market's show must start more than an hour from now and within the `max_days_ahead` that `GET /concert_cancellation_markets/availability` reports. A market is traded through RFQs: pass the returned `market_ticker` to `POST /communications/rfqs`. These markets are in series starting with `KXRFQ` and are left out of unscoped market listings. A market created a moment ago may not be readable yet: if `GET /markets/{ticker}` returns 404 right after creation, retry. Errors carry the specific reason in `details`: | Status | `code` | When | | --- | --- | --- | | 400 | `bad_request` | The body isn't valid JSON, or a field has the wrong type. | | 400 | `missing_parameters` | A required field is missing or empty. | | 400 | `invalid_parameters` | A field is present but unusable: an unknown cover, a `jambase_event_id` that isn't `jambase:`, a `scheduled_date` that isn't YYYY-MM-DD, or a show scheduled further ahead than `max_days_ahead`. | | 404 | `not_found` | The listing source has no show with that id. | | 409 | `concert_cancellation_market_unavailable` | The request is valid but the market isn't offered: concert markets or the cover are switched off, the show is now listed on another date, has already been canceled or postponed, starts too soon, isn't a concert, or its market has closed. | | 429 | `concert_cancellation_market_limit_exceeded` | The daily limit on new concert markets across all users was reached. Retrying at once doesn't help. | | 429 | `too_many_requests` | Your API rate limit. This endpoint is charged against your write budget. | operationId: CreateConcertCancellationMarket requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CreateConcertCancellationMarketRequest' responses: '200': description: Market returned or created successfully content: application/json: schema: $ref: '#/components/schemas/CreateConcertCancellationMarketResponse' '400': $ref: '#/components/responses/BadRequestError' '401': $ref: '#/components/responses/UnauthorizedError' '403': $ref: '#/components/responses/ForbiddenError' '404': $ref: '#/components/responses/NotFoundError' '409': $ref: '#/components/responses/ConflictError' '429': $ref: '#/components/responses/RateLimitError' '500': $ref: '#/components/responses/InternalServerError' security: - kalshiAccessKey: [] kalshiAccessSignature: [] kalshiAccessTimestamp: [] components: schemas: CreateConcertCancellationMarketRequest: type: object required: - jambase_event_id - scheduled_date - cover properties: jambase_event_id: type: string description: The show, as `jambase:`, from the concert listing or search. example: jambase:16543035 x-oapi-codegen-extra-tags: validate: required scheduled_date: type: string description: >- The venue-local date the show is scheduled for, as YYYY-MM-DD. It must match the show's current listing. example: '2026-11-20' x-oapi-codegen-extra-tags: validate: required,datetime=2006-01-02 cover: $ref: '#/components/schemas/ConcertCover' CreateConcertCancellationMarketResponse: type: object required: - cover - event_ticker - market_ticker - created properties: cover: $ref: '#/components/schemas/ConcertCover' event_ticker: type: string description: Event ticker of the market. example: KXRFQCONCERTP-JB16543035-26NOV20 market_ticker: type: string description: Market ticker of the market. example: KXRFQCONCERTP-JB16543035-26NOV20-PPD created: type: boolean description: False when a market for the same request already existed. ConcertCover: type: string enum: - postponed - cancelled - either x-enum-varnames: - ConcertCoverPostponed - ConcertCoverCancelled - ConcertCoverEither description: | What a concert cancellation market pays on, read from the show's listing after its scheduled date has ended: - `postponed`: Yes when the show is listed as postponed, or as taking place on any other date. A show listed as canceled resolves to No. - `cancelled`: Yes when the show is listed as canceled. - `either`: Yes in both of those cases. ErrorResponse: type: object properties: code: type: string description: Error code message: type: string description: Human-readable error message details: type: string description: Additional details about the error, if available responses: BadRequestError: description: Bad request - invalid input content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' UnauthorizedError: description: Unauthorized - authentication required content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' ForbiddenError: description: Forbidden - insufficient permissions content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' NotFoundError: description: Resource not found content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' ConflictError: description: Conflict - resource already exists or cannot be modified content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' RateLimitError: description: >- Rate limit exceeded. The default cost is 10 tokens per request. Use GET /trade-api/v2/account/endpoint_costs to list non-default endpoint costs. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' InternalServerError: description: Internal server error content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' securitySchemes: kalshiAccessKey: type: apiKey in: header name: KALSHI-ACCESS-KEY description: Your API key ID kalshiAccessSignature: type: apiKey in: header name: KALSHI-ACCESS-SIGNATURE description: >- Base64 signature of the pre-sign text (timestamp + method + path) made with the API key's algorithm - RSA-PSS with SHA-256 for RSA keys, Ed25519 for Ed25519 keys kalshiAccessTimestamp: type: apiKey in: header name: KALSHI-ACCESS-TIMESTAMP description: Request timestamp in milliseconds ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.