Castor Users API

Users and study membership.

Work with this as data

Every API here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for apis

7 MCP tools reach this
  • find_apisBrowse and filter every API in the catalog.
  • get_api_artifactsOne API's artifacts, grouped by type.
  • get_openapiThe primary OpenAPI for this API.
  • find_similar_apisAPIs that look like this one.
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
All 92 tools

Call it yourself

curl for this page
This API
curl "https://apis.io/api/v1/apis/castoredc-users-api"
All apis
curl "https://apis.io/api/v1/apis?limit=25"

Discovery needs no key. Ratings and market analysis are Pro.

Get an API key

Free tier, no email required.

A second provider on the same verified email joins the account you already have.

OpenAPI Specification

castoredc-users-api-openapi.yml Raw ↑
openapi: 3.0.3
info:
  title: Castor EDC / CDMS Audit Trail Users API
  description: 'The Castor EDC / CDMS API is a RESTful interface to Castor''s cloud electronic data capture (EDC) and clinical data management platform. It exposes study configuration and collected data - studies, participants (records), institutes (sites), users, fields and field metadata, study data points, repeating data (reports), surveys and survey packages, the audit trail, and batch data export. Authentication is OAuth2 with the Client Credentials flow: request an access token from POST /oauth/token using an API Client ID and Client Secret generated in Castor User Settings, then send it as a Bearer token. Access tokens are valid for 5 hours. Most identifiers (study, field, report / repeating-data instance, survey package instance) are uppercase GUIDs in 8-4-4-4-12 format; the participant ID is the exception.


    Endpoint status: paths that this document marks with `x-endpoint-status: confirmed` were observed directly in Castor''s published API reference and helpdesk documentation. Paths marked `x-endpoint-status: modeled` reflect the documented resource model and the coverage of the official R and Python wrapper packages, but the exact path or shape was inferred and should be verified against https://data.castoredc.com/api during reconciliation.'
  version: '1.0'
  contact:
    name: Castor
    url: https://www.castoredc.com
  license:
    name: Proprietary
    url: https://www.castoredc.com/legal/
servers:
- url: https://data.castoredc.com/api
  description: Castor EU (default)
- url: https://us.castoredc.com/api
  description: Castor US region
security:
- oauth2ClientCredentials: []
tags:
- name: Users
  description: Users and study membership.
paths:
  /user:
    get:
      operationId: listUsers
      tags:
      - Users
      summary: List users
      description: Lists the users the authenticated account can access.
      x-endpoint-status: confirmed
      responses:
        '200':
          description: A list of users.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UserCollection'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /user/{user_id}:
    get:
      operationId: getUser
      tags:
      - Users
      summary: Retrieve a user
      description: Retrieves a single user by ID.
      x-endpoint-status: confirmed
      parameters:
      - $ref: '#/components/parameters/UserId'
      responses:
        '200':
          description: A user.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/User'
        '404':
          $ref: '#/components/responses/NotFound'
  /study/{study_id}/user:
    get:
      operationId: listStudyUsers
      tags:
      - Users
      summary: List study users
      description: Lists the users who are members of a given study.
      x-endpoint-status: confirmed
      parameters:
      - $ref: '#/components/parameters/StudyId'
      responses:
        '200':
          description: A list of study users.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UserCollection'
components:
  schemas:
    User:
      type: object
      properties:
        id:
          type: string
          format: uuid
        name:
          type: string
        email_address:
          type: string
        institute:
          type: string
    UserCollection:
      type: object
      properties:
        _embedded:
          type: object
          properties:
            user:
              type: array
              items:
                $ref: '#/components/schemas/User'
  responses:
    NotFound:
      description: The requested resource was not found.
    Unauthorized:
      description: Missing or invalid access token.
  parameters:
    UserId:
      name: user_id
      in: path
      required: true
      description: The user GUID.
      schema:
        type: string
    StudyId:
      name: study_id
      in: path
      required: true
      description: The study GUID (uppercase, 8-4-4-4-12 format).
      schema:
        type: string
  securitySchemes:
    oauth2ClientCredentials:
      type: oauth2
      flows:
        clientCredentials:
          tokenUrl: https://data.castoredc.com/api/oauth/token
          scopes: {}