# Green Button Connect My Data (CMD) ESPI Resource Server API

**Canonical:** https://apis.io/apis/green-button-alliance/green-button-connect-my-data-api/  
**Provider:** Green Button Alliance — https://apis.io/providers/green-button-alliance/  
**Base URL:** https://sandbox.greenbuttonalliance.org:8443/DataCustodian  
**Documentation:** https://greenbuttonalliance.github.io/OpenESPI-GreenButton-API-Documentation/API/

Green Button Connect My Data (CMD) ESPI Resource Server API is one of 3 APIs that [Green Button Alliance](https://apis.io/providers/green-button-alliance/) publishes on the [APIs.io](https://apis.io/) network, described by a machine-readable OpenAPI specification. Tagged areas include Green Button, Connect My Data, ESPI, Energy, and Usage Data. The published artifact set on APIs.io includes an OpenAPI specification, an API reference, and API documentation.

The Green Button Connect My Data resource server API as specified by the Green Button Alliance against NAESB REQ.21 ESPI 4.0 — read access to ApplicationInformation, Authorization, UsagePoint and bulk Batch resources under /espi/1_1/resource, returned as ESPI/Atom XML and protected by OAuth 2.0 (authorization code and client credentials). GBA publishes the contract openly under Apache 2.0 on GitHub; the only base URL documented in it is GBA's own ESPI sandbox, which returned HTTP 403 to anonymous probes on 2026-07-27 and which GBA states is unavailable pending a new platform in 2026Q3. This is a specification of the interface every certified Data Custodian implements, not a live service run by GBA.

## Machine-readable artifacts (12)

- **OpenAPI** — https://raw.githubusercontent.com/api-evangelist/green-button-alliance/refs/heads/main/openapi/green-button-alliance-green-button-api-openapi.yml
- **OpenAPI** — https://raw.githubusercontent.com/api-evangelist/green-button-alliance/refs/heads/main/openapi/green-button-alliance-application-information-openapi.yml
- **Overlay** — https://raw.githubusercontent.com/api-evangelist/green-button-alliance/refs/heads/main/overlays/green-button-alliance-green-button-api-overlay.yaml
- **Overlay** — https://raw.githubusercontent.com/api-evangelist/green-button-alliance/refs/heads/main/overlays/green-button-alliance-application-information-overlay.yaml
- **Examples** — https://raw.githubusercontent.com/api-evangelist/green-button-alliance/refs/heads/main/examples/_index.yml
- **APIReference** — https://greenbuttonalliance.github.io/OpenESPI-GreenButton-API-Documentation/API/
- **Documentation** — https://www.greenbuttonalliance.org/green-button-connect-my-data-cmd
- **Documentation** — https://www.greenbuttonalliance.org/developer-resources
- **Repository** — https://github.com/GreenButtonAlliance/OpenAPI-Green-Button-Documentation
- **Repository** — https://github.com/GreenButtonAlliance/OpenESPI-DataCustodian-java
- **Specification** — https://www.naesb.org/espi_standards.asp
- **APIsJSON** — https://raw.githubusercontent.com/api-evangelist/green-button-alliance/refs/heads/main/apis.yml

## Other Green Button Alliance APIs (2)

- [Green Button Third Party (OpenESPI) API](https://apis.io/apis/green-button-alliance/green-button-third-party-api/)
- [Green Button Alliance OpenESPI Authorization Server API](https://apis.io/apis/green-button-alliance/green-button-alliance-authorization-server-openapi/)

## Tags

Green Button, Connect My Data, ESPI, Energy, Usage Data, Authentication

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/green-button-alliance/green-button-connect-my-data-api/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/green-button-alliance/.