# ISO New England

> ISO New England Inc. is the independent, nonprofit regional transmission organization (RTO) authorized by the Federal Energy Regulatory Commission to operate the high-voltage power system, administer the wholesale electricity markets, and plan the power system for Connecticut, Rhode Island, Massachusetts, Vermont, New Hampshire and most of Maine. It publishes one documented programmatic contract - the Web Services API v1.1 - a read-only RESTful interface of 489 documented GET path templates across 91 market and operations resources, in XML or JSON. The API requires HTTP Basic authentication over SSL using a free, self-serve ISO Express account; anonymous calls return HTTP 401. The same market and system data is also downloadable anonymously as bulk CSV from ISO Express. ISO New England holds no retail customer relationships, so there is no consumer, usage, billing or Green Button data surface of any kind.

Generated by the API Evangelist enrichment pipeline on 2026-07-27. ISO New England does not publish an llms.txt (https://www.iso-ne.com/llms.txt -> 404, https://webservices.iso-ne.com/llms.txt -> 404), so this file is generated from apis.yml and the artifacts in this repository. Provenance: every artifact below is labelled searched (harvested from ISO New England), probed (live measurement), derived (computed from harvested artifacts) or generated (authored by API Evangelist).

## API

- [ISO New England Web Services API v1.1](https://webservices.iso-ne.com/docs/v1.1/): Base path https://webservices.iso-ne.com/api/v1.1. Read-only energy and market data - five-minute and hourly LMPs, day-ahead and real-time demand, generation fuel mix, system load, external interchange and flows, constraints, operating reserve and reserve prices, regulation clearing prices, Forward Capacity Market auction and reconfiguration results, FTR auction clearing prices, NCPC, outages, seven-day and wind forecasts, load forecasts, power system status, demand response dispatch and price-response events, locations, and hourly-bid participant resources.
- Authentication: HTTP Basic over SSL. Credentials come from a free ISO Express account; ISO New England states account holders are automatically granted access to the public data feeds.
- Formats: XML and JSON, selected by a .xml/.json extension on the request URL or by an Accept header.

## Specs and schemas

- [OpenAPI 3.1 (derived)](openapi/iso-new-england-web-services-openapi.yml): 489 operations, 217 schemas, 91 tags. DERIVED by API Evangelist from ISO New England's published Enunciate documentation and XSDs - ISO New England does not publish an OpenAPI. Each operation carries x-evidence naming the exact documentation page it came from.
- [XML Schema ns0.xsd (searched, verbatim)](schemas/iso-new-england-web-services-ns0.xsd): https://webservices.iso-ne.com/docs/v1.1/ns0.xsd - 205 complex types.
- [XML Schema ns1.xsd (searched, verbatim)](schemas/iso-new-england-web-services-ns1.xsd): https://webservices.iso-ne.com/docs/v1.1/ns1.xsd.
- [NEXTT external transaction XSD (searched, verbatim)](schemas/nextt-web-services.xsd): https://www.iso-ne.com/static-assets/documents/2019/09/nextt-web-services.xsd.
- [JSON Schema 2020-12 (derived)](json-schema/iso-new-england-web-services-schemas.json): the same 217 data types as JSON Schema.
- WADL (published but gated): https://webservices.iso-ne.com/api/v1.1?_wadl&_type=xml returns 401 anonymously.

## Artifacts in this repository

- [Authentication profile (derived)](authentication/iso-new-england-authentication.yml)
- [API conventions (searched)](conventions/iso-new-england-conventions.yml): content negotiation, path patterns, /info freshness endpoints, no pagination, no idempotency key, no documented rate limits.
- [Controlled vocabularies (searched)](vocabulary/iso-new-england-vocabulary.yml): load zones, dispatch zones, external nodes, reserve and capacity zones, interfaces, NCPC types, fuel categories, bid types, ARA, market types, outage/equipment/company/status codes, plus the live 1,302-entry location registry.
- [Data model (derived)](data-model/iso-new-england-data-model.yml): 217 entities, 174 relationships.
- [Error catalog (derived)](errors/iso-new-england-problem-types.yml): HTTP statuses only - no problem+json, no error-code registry published.
- [Lifecycle (searched)](lifecycle/iso-new-england-lifecycle.yml): v1.1 since November 2013; no deprecation policy, no SLA, no API status page.
- [Changelog (searched)](changelog/iso-new-england-changelog.yml): the provider's dated statements - Batteries fuel category May 2026, documentation spreadsheet July 2025, v1.1 November 2013.
- [Conformance (derived)](conformance/iso-new-england-conformance.yml): what the API does and does not conform to, plus the FERC/NERC/NPCC regimes.
- [Domain security (probed)](security/iso-new-england-domain-security.yml): TLSv1.3 + HSTS on both hosts; no DNSSEC, no CAA; SPF and DMARC (quarantine).
- [Well-known surface (probed)](well-known/iso-new-england-well-known.yml): every /.well-known probe returned 404.
- [Packages (searched)](packages/iso-new-england-packages.yml): no first-party SDK; third-party leads only (gridstatus, isodata, pyiso).
- [MCP candidate (derived)](mcp/iso-new-england-mcp.yml): no MCP server exists; a 22-tool candidate list bound to real operationIds.
- [Agentic access (generated)](agentic-access/iso-new-england-agentic-access.yml): recommended x-agentic-access contracts for all 489 read operations.
- [Agent skills (generated)](skills/_index.yml)
- [Real response examples (searched)](examples/_index.yml): 14 real payloads observed anonymously on 2026-07-27.
- [Overlay (generated)](overlays/iso-new-england-web-services-overlay.yaml)

## Documentation

- [Web Services Data](https://www.iso-ne.com/participate/support/web-services-data): canonical prose documentation, WADL location, formats, and the full parameter tables.
- [API reference](https://webservices.iso-ne.com/docs/v1.1/): Enunciate-generated technical documentation, one page per path template.
- [Requests to Access Software and Systems](https://www.iso-ne.com/participate/applications-status-changes/access-software-systems): the access rule for data feeds.
- [ISO Express sign-up](https://www.iso-ne.com/signup): free, self-serve account.
- [ISO Express](https://www.iso-ne.com/isoexpress/): public dashboards, report trees, and anonymous bulk CSV downloads.
- [Business documentation spreadsheet](https://www.iso-ne.com/static-assets/documents/2017/06/webservices_documentation.xlsx): every report, its web service address and parameters.
- [Ask ISO support](https://askiso.iso-ne.com/s/)
- [ISO Newswire](https://isonewswire.com/) and its [RSS feed](https://isonewswire.com/feed/)

## What does not exist

- No consumer, usage, billing, account or premise data, and no consent or data-portability surface. ISO New England does not handle retail electricity and no Green Button / NAESB ESPI mandate reaches it.
- No OpenAPI, Postman collection, SDK, CLI, sandbox, webhook, streaming feed or AsyncAPI published by ISO New England.
- No /.well-known documents, no security.txt, no trust centre, no bug bounty, no published information-security certifications.
- No rate limits, quotas or throttling headers documented.