openapi: 3.1.0
info:
  title: Meditech Expanse FHIR R4 Allergy Observation API
  description: Meditech Expanse FHIR API enables standards-based interoperability for sharing patient data across healthcare systems. Supports TEFCA-aligned data exchange through the Traverse Exchange national network, connecting over 700 facilities across 41 US states. Built on HL7 FHIR R4 standards.
  version: 4.0.0
  contact:
    name: Meditech Support
    url: https://ehr.meditech.com/contact
  license:
    name: Proprietary
    url: https://ehr.meditech.com/privacy-policy
servers:
- url: https://{facility}.meditech.com/fhir/r4
  variables:
    facility:
      default: yourhospital
      description: Your Meditech facility subdomain
security:
- SMART_OAuth2:
  - patient/*.read
  - user/*.read
  - launch
tags:
- name: Observation
  description: Vital signs and laboratory results
paths:
  /Patient/{id}/Observation:
    get:
      operationId: getPatientObservations
      summary: Get patient observations (vital signs, lab results)
      description: Retrieve clinical observations for a patient including vital signs, laboratory results, and other measurements.
      tags:
      - Observation
      parameters:
      - name: id
        in: path
        required: true
        schema:
          type: string
      - name: category
        in: query
        schema:
          type: string
        description: Filter by category (vital-signs, laboratory, imaging, etc.)
      - name: code
        in: query
        schema:
          type: string
        description: LOINC code filter
      - name: date
        in: query
        schema:
          type: string
        description: Date range (e.g., date=ge2024-01-01&date=le2024-12-31)
      - name: _count
        in: query
        schema:
          type: integer
          default: 100
      responses:
        '200':
          description: Bundle of Observation resources
          content:
            application/fhir+json:
              schema:
                $ref: '#/components/schemas/Bundle'
components:
  schemas:
    Bundle:
      type: object
      description: FHIR Bundle resource
      properties:
        resourceType:
          type: string
          enum:
          - Bundle
        id:
          type: string
        type:
          type: string
          enum:
          - searchset
          - collection
          - transaction
          - batch
          - history
        total:
          type: integer
        link:
          type: array
          items:
            type: object
            properties:
              relation:
                type: string
              url:
                type: string
        entry:
          type: array
          items:
            type: object
            properties:
              fullUrl:
                type: string
              resource:
                type: object
                additionalProperties: true
  securitySchemes:
    SMART_OAuth2:
      type: oauth2
      description: SMART on FHIR OAuth 2.0 authorization
      flows:
        authorizationCode:
          authorizationUrl: https://yourhospital.meditech.com/oauth/authorize
          tokenUrl: https://yourhospital.meditech.com/oauth/token
          scopes:
            patient/*.read: Read access to all patient-owned resources
            user/*.read: Practitioner read access to all resources
            launch: EHR launch context
            openid: OpenID Connect identity
            fhirUser: FHIR user claim
externalDocs:
  description: Meditech Interoperability Documentation
  url: https://ehr.meditech.com/ehr-solutions/meditech-interoperability