Cadence Design Systems

MMDS — Macromolecular Data Service

A live HTTPS JSON API for macromolecular experimental data — experiments, sites, families, contexts, frames and results, keyed on PDB structure codes with .pdb/.cif structures, MTZ density and cryo-EM maps. Operated by OpenEye, Cadence Molecular Sciences, and reachable at https://mmds.eyesopen.com/api/v1/ — an unauthenticated GET on 2026-09-05 returned HTTP 403 with a Django REST Framework body, {"detail":"Authentication credentials were not provided."}, which confirms the service is real and that every path is authentication-gated. No OpenAPI is published; the mmdsclient Python library and mmdscli CLI are the published interface.

Documentation GitHub

Documentation

📖

Documentation

https://docs.eyesopen.com/webservices/mmds/

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APIReference

https://docs.eyesopen.com/webservices/mmds/client.html

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GettingStarted

https://docs.eyesopen.com/webservices/mmds/quickstart.html

📖

Authentication

https://raw.githubusercontent.com/api-evangelist/cadence/refs/heads/main/authentication/cadence-authentication.yml

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API entry from apis.yml

aid: cadence:mmds
name: MMDS — Macromolecular Data Service
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/cadence.png
tags:
- Structural Biology
- Protein Data
- Scientific Computing
- Drug Discovery
humanURL: https://docs.eyesopen.com/webservices/mmds/
baseURL: https://mmds.eyesopen.com/api/v1/
properties:
- type: Documentation
  url: https://docs.eyesopen.com/webservices/mmds/
- type: APIReference
  url: https://docs.eyesopen.com/webservices/mmds/client.html
- type: GettingStarted
  url: https://docs.eyesopen.com/webservices/mmds/quickstart.html
- type: Authentication
  url: authentication/cadence-authentication.yml
description: A live HTTPS JSON API for macromolecular experimental data — experiments, sites, families,
  contexts, frames and results, keyed on PDB structure codes with .pdb/.cif structures, MTZ density and
  cryo-EM maps. Operated by OpenEye, Cadence Molecular Sciences, and reachable at https://mmds.eyesopen.com/api/v1/
  — an unauthenticated GET on 2026-09-05 returned HTTP 403 with a Django REST Framework body, {"detail":"Authentication
  credentials were not provided."}, which confirms the service is real and that every path is authentication-gated.
  No OpenAPI is published; the mmdsclient Python library and mmdscli CLI are the published interface.