openapi: 3.2.0 info: title: ISO New England Web Services API v1.1 Hbfcmara API version: '1.1' description: RESTful interface to ISO New England energy and market data. This OpenAPI document was DERIVED by API Evangelist from ISO New England's own published, machine-generated Enunciate technical documentation at https://webservices.iso-ne.com/docs/v1.1/ and the two XML Schemas it publishes (ns0.xsd, ns1.xsd, saved verbatim under schemas/). ISO New England does not publish an OpenAPI definition; the only provider-published machine-readable description of the interface is a WADL at https://webservices.iso-ne.com/api/v1.1?_wadl&_type=xml, which sits behind the same HTTP Basic authentication as the API and returned HTTP 401 to anonymous probes. Every path, method, parameter, description, media type and schema in this document is copied from the provider's published sources; nothing was invented. Each operation carries x-evidence naming the exact documentation page it came from. All feeds are available in XML and JSON, selected by adding a .xml or .json extension to the request URL or by sending an Accept header of application/xml or application/json. contact: name: ISO New England Ask ISO url: https://askiso.iso-ne.com/s/ x-provenance: method: derived derived_by: API Evangelist enrichment pipeline derived_on: '2026-07-27' sources: - https://webservices.iso-ne.com/docs/v1.1/ - https://webservices.iso-ne.com/docs/v1.1/ns0.xsd - https://webservices.iso-ne.com/docs/v1.1/ns1.xsd - https://www.iso-ne.com/participate/support/web-services-data not_provider_published: true note: Derived from provider-published HTML documentation and XSDs. Not an ISO New England artifact. servers: - url: https://webservices.iso-ne.com/api/v1.1 description: Production base path (HTTP Basic over SSL) security: - basicAuth: [] tags: - name: hbfcmara description: 5 path template(s) under /hbfcmara in the published ISO New England Web Services API v1.1 documentation. paths: /hbfcmara: get: operationId: getHbfcmara summary: Default resource description: Default resource. Redirects to FCM Annual Reconfiguration Auction Historical Bids Info. tags: - hbfcmara responses: '200': description: Successful response. content: application/xml: schema: description: Response payload is not described in the published documentation. application/json: schema: description: Response payload is not described in the published documentation. '401': description: Unauthorized - HTTP Basic credentials from an ISO Express account are required. Verified by anonymous probe on 2026-07-27. x-evidence: source: https://webservices.iso-ne.com/docs/v1.1/rest.hbfcmara.html harvested: '2026-07-27' /hbfcmara/cp/{cp}: get: operationId: getHbfcmaraCpByCp summary: Get an entire days Annual Reconfiguration Auction Historical Bids for a given cp description: Get an entire days Annual Reconfiguration Auction Historical Bids for a given cp. tags: - hbfcmara responses: '200': description: a HbfcmarasElement containing the Annual Reconfiguration Auction Historical Bids. content: application/xml: schema: $ref: '#/components/schemas/Hbfcmaras' application/json: schema: $ref: '#/components/schemas/Hbfcmaras' '401': description: Unauthorized - HTTP Basic credentials from an ISO Express account are required. Verified by anonymous probe on 2026-07-27. x-evidence: source: https://webservices.iso-ne.com/docs/v1.1/rest.hbfcmara.cp.cp.html harvested: '2026-07-27' x-xml-element: Hbfcmaras parameters: - name: cp in: path required: true schema: type: string description: The cp to retrieve data for (YYYY-YY) /hbfcmara/cp/{cp}/ara/{ara}: get: operationId: getHbfcmaraCpByCpAraByAra summary: Get an entire days Annual Reconfiguration Auction Historical Bids for a given cp and ara description: Get an entire days Annual Reconfiguration Auction Historical Bids for a given cp and ara. tags: - hbfcmara responses: '200': description: a HbfcmarasElement containing the Annual Reconfiguration Auction Historical Bids. content: application/xml: schema: $ref: '#/components/schemas/Hbfcmaras' application/json: schema: $ref: '#/components/schemas/Hbfcmaras' '401': description: Unauthorized - HTTP Basic credentials from an ISO Express account are required. Verified by anonymous probe on 2026-07-27. x-evidence: source: https://webservices.iso-ne.com/docs/v1.1/rest.hbfcmara.cp.cp.ara.ara.html harvested: '2026-07-27' x-xml-element: Hbfcmaras parameters: - name: cp in: path required: true schema: type: string description: The day to retrieve data for (YYYY-YY) - name: ara in: path required: true schema: type: string description: The ara /hbfcmara/current: get: operationId: getHbfcmaraCurrent summary: Get the current Annual Reconfiguration Auction Historical Bids for Hub, Load Zones, and External Nodes description: Get the current Annual Reconfiguration Auction Historical Bids for Hub, Load Zones, and External Nodes. tags: - hbfcmara responses: '200': description: a HbfcmarasElement containing the current Annual Reconfiguration Auction Historical Bids. content: application/xml: schema: $ref: '#/components/schemas/Hbfcmaras' application/json: schema: $ref: '#/components/schemas/Hbfcmaras' '401': description: Unauthorized - HTTP Basic credentials from an ISO Express account are required. Verified by anonymous probe on 2026-07-27. x-evidence: source: https://webservices.iso-ne.com/docs/v1.1/rest.hbfcmara.current.html harvested: '2026-07-27' x-xml-element: Hbfcmaras /hbfcmara/info: get: operationId: getHbfcmaraInfo summary: Get the Service Info for Annual Reconfiguration Auction Historical Bids description: Get the Service Info for Annual Reconfiguration Auction Historical Bids. tags: - hbfcmara responses: '200': description: the ServiceInfoElement for FCM Annual Reconfiguration Auction Historical Bids. content: application/xml: schema: $ref: '#/components/schemas/ServiceInfo' application/json: schema: $ref: '#/components/schemas/ServiceInfo' '401': description: Unauthorized - HTTP Basic credentials from an ISO Express account are required. Verified by anonymous probe on 2026-07-27. x-evidence: source: https://webservices.iso-ne.com/docs/v1.1/rest.hbfcmara.info.html harvested: '2026-07-27' x-xml-element: ServiceInfo components: schemas: ServiceInfo: type: object properties: LatestBeginDate: type: string format: date-time CreationDate: type: string format: date-time required: - LatestBeginDate - CreationDate x-xsd-source: schemas/iso-new-england-web-services-ns0.xsd#type_ServiceInfo Hbfcmaras: type: object properties: Hbfcmara: type: array items: $ref: '#/components/schemas/Hbfcmara' x-xsd-source: schemas/iso-new-england-web-services-ns0.xsd#type_Hbfcmaras Hbfcmara: type: object properties: Cp: type: string AucType: type: string MaskResID: type: number MaskLPID: type: number MaskCZID: type: number ResType: type: string MaskIntfcID: type: number BidType: type: string Seg1Mw: type: number Seg1Price: type: number Seg2Mw: type: number Seg2Price: type: number Seg3Mw: type: number Seg3Price: type: number Seg4Mw: type: number Seg4Price: type: number Seg5Mw: type: number Seg5Price: type: number required: - Cp x-xsd-source: schemas/iso-new-england-web-services-ns0.xsd#type_Hbfcmara securitySchemes: basicAuth: type: http scheme: basic description: HTTP Basic Authentication over SSL. Credentials come from a free, self-serve ISO Express account; ISO New England states that ISO Express account holders are automatically granted access to the public data feeds. See https://www.iso-ne.com/participate/applications-status-changes/access-software-systems