openapi: 3.1.0
info:
  title: HL7 FHIR R4 Healthcare Bundle Encounter API
  description: HL7 FHIR R4 (v4.0.1) RESTful API for healthcare data exchange. Provides access to patient demographics, clinical observations, conditions, medications, encounters, care plans, and diagnostic reports. Implements the FHIR REST specification including CRUD operations, search parameters, history, and batch/ transaction bundles. SMART on FHIR OAuth 2.0 authorization required.
  version: 4.0.1
  contact:
    name: HL7 International
    url: https://www.hl7.org/fhir/
  license:
    name: Creative Commons CC0
    url: https://creativecommons.org/publicdomain/zero/1.0/
servers:
- url: https://fhir-server.example.com/fhir/R4
  description: FHIR R4 server base URL (replace with actual server URL)
security:
- SMARTonFHIR: []
tags:
- name: Encounter
  description: Patient visits and encounters
paths:
  /Encounter:
    get:
      operationId: searchEncounter
      summary: Search encounters
      description: Searches for Encounter resources (visits, hospitalizations, telehealth) for a patient.
      tags:
      - Encounter
      parameters:
      - name: patient
        in: query
        schema:
          type: string
      - name: status
        in: query
        schema:
          type: string
          enum:
          - planned
          - arrived
          - triaged
          - in-progress
          - onleave
          - finished
          - cancelled
      - name: class
        in: query
        schema:
          type: string
        description: Encounter class code (AMB, IMP, EMER, etc.)
      - name: date
        in: query
        schema:
          type: string
      - name: _count
        in: query
        schema:
          type: integer
          default: 20
      responses:
        '200':
          description: Bundle of Encounter resources returned
          content:
            application/fhir+json:
              schema:
                $ref: '#/components/schemas/Bundle'
components:
  schemas:
    Bundle:
      type: object
      description: A container for a collection of FHIR resources
      properties:
        resourceType:
          type: string
          enum:
          - Bundle
        id:
          type: string
        type:
          type: string
          enum:
          - document
          - message
          - transaction
          - transaction-response
          - batch
          - batch-response
          - history
          - searchset
          - collection
        total:
          type: integer
          description: Total number of matches (for searchset bundles)
        link:
          type: array
          items:
            type: object
            properties:
              relation:
                type: string
                enum:
                - self
                - first
                - previous
                - next
                - last
              url:
                type: string
                format: uri
        entry:
          type: array
          items:
            type: object
            properties:
              fullUrl:
                type: string
                format: uri
              resource:
                type: object
                description: FHIR resource (any type)
              search:
                type: object
                properties:
                  mode:
                    type: string
                    enum:
                    - match
                    - include
                    - outcome
                  score:
                    type: number
              request:
                type: object
                properties:
                  method:
                    type: string
                    enum:
                    - GET
                    - HEAD
                    - POST
                    - PUT
                    - DELETE
                    - PATCH
                  url:
                    type: string
              response:
                type: object
                properties:
                  status:
                    type: string
                  location:
                    type: string
      required:
      - resourceType
      - type
  securitySchemes:
    SMARTonFHIR:
      type: oauth2
      description: SMART on FHIR OAuth 2.0 authorization
      flows:
        authorizationCode:
          authorizationUrl: https://auth.example.com/authorize
          tokenUrl: https://auth.example.com/token
          scopes:
            patient/Patient.read: Read patient data
            patient/Observation.read: Read observations
            patient/Condition.read: Read conditions
            patient/MedicationRequest.read: Read medication requests
            patient/Encounter.read: Read encounters
            launch/patient: Patient context launch
            openid: OpenID Connect identity
externalDocs:
  description: HL7 FHIR R4 Specification
  url: https://www.hl7.org/fhir/R4/