generated: '2026-09-06'
method: searched
source: >-
  npm registry search, PyPI, github.com/utilityapi, and the Consumers Energy Green Button and
  platform documentation
description: >-
  Client-library search for the CMS Energy / Consumers Energy API surface. NO first-party SDK
  exists. Neither CMS Energy nor Consumers Energy publishes a client library in any registry, and
  the platform that operates the Green Button Connect My Data program for them publishes none
  either — its GitHub organization (github.com/utilityapi, HTTP 200) has zero public
  repositories. Every package below is community-written and is recorded as such.
official_sdk_count: 0
registries_searched:
  - registry: npm
    queries: [utilityapi, utility-api, greenbutton, green-button, espi]
    first_party_hits: 0
  - registry: PyPI
    queries: [utilityapi, greenbutton]
    result: >-
      404 for both. `utility-api` exists on PyPI (HTTP 200) but is an unrelated generic helper
      package, not a client for this API.
    first_party_hits: 0
  - registry: GitHub
    org: https://github.com/utilityapi
    result: Organization exists, 0 public repositories.
    first_party_hits: 0
  - registry: pkg.go.dev / crates.io / NuGet / Maven Central / RubyGems / Packagist
    result: Not searched individually — no SDK is referenced anywhere in the provider docs to search for.
    first_party_hits: 0
packages:
  - name: '@cityssm/green-button-subscriber'
    registry: npm
    url: https://www.npmjs.com/package/@cityssm/green-button-subscriber
    official: false
    author: City of Sault Ste. Marie (third party, unaffiliated)
    language: JavaScript/TypeScript
    covers: Green Button Connect My Data subscriber flow (ESPI), generic across data custodians.
    version: 0.5.0
    published: '2023-10-05'
    version_source: https://registry.npmjs.org/@cityssm/green-button-subscriber
    note: >-
      Not a Consumers Energy client. Listed because it is the only maintained npm package that
      implements the GBCMD/ESPI subscriber side an integrator would otherwise write by hand.
  - name: '@cityssm/green-button-parser'
    registry: npm
    url: https://www.npmjs.com/package/@cityssm/green-button-parser
    official: false
    author: City of Sault Ste. Marie (third party, unaffiliated)
    language: JavaScript/TypeScript
    covers: Parsing Green Button ESPI Atom XML payloads.
    version: 1.0.1
    published: '2025-10-14'
    version_source: https://registry.npmjs.org/-/v1/search?text=green-button
finding: >-
  A first-party SDK whose release date lags the API is the strongest abandonment signal this
  pipeline collects. Here there is no first-party SDK at all, which is a different and more
  basic gap: an integrator building against the Consumers Energy Green Button program writes
  their own HTTP and their own ESPI Atom XML parsing, or adopts an unaffiliated community
  library last published in 2023.