openapi: 3.1.0
info:
  title: Cigna Drug Formulary Bulk Data ExplanationOfBenefit API
  description: Public FHIR-based Drug Formulary API exposing Cigna's covered drug lists, formulary tiers, prior authorization, step therapy, and quantity limits. Implements the HL7 Da Vinci PDex US Drug Formulary IG required by the CMS Interoperability and Patient Access rule.
  version: '1.0'
  contact:
    name: Cigna Developer Support
    url: https://developer.cigna.com/support
servers:
- url: https://fhir.cigna.com/DrugFormulary/v1
  description: Cigna Drug Formulary Production
tags:
- name: ExplanationOfBenefit
paths:
  /ExplanationOfBenefit:
    get:
      operationId: searchExplanationOfBenefit
      summary: Retrieve EOB claims data for the authenticated member
      tags:
      - ExplanationOfBenefit
      parameters:
      - name: patient
        in: query
        schema:
          type: string
      responses:
        '200':
          description: FHIR Bundle of ExplanationOfBenefit resources
externalDocs:
  description: Cigna Service APIs
  url: https://developer.cigna.com/docs/service-apis