Implement ACORD CSIO JSON API standards for real-time First Notice of Loss data exchange between a broker management system and a carrier

Verified steps

1. Review the CSIO JSON API Standards for the FNOL use case published by the Centre for Study of Insurance Operations; the standard defines the request/response schema, authentication requirements, and endpoint conventions
2. Configure mutual OAuth 2.0 authentication between the broker management system (BMS) and the carrier API endpoint; CSIO API Security Standards specify the required auth mechanism
3. At claim event, extract FNOL data from the BMS: policy number, date/time of loss, loss location, claimant details, and brief loss description; map fields to the CSIO FNOL JSON schema
4. POST the FNOL payload to the carrier's CSIO-compliant FNOL endpoint; the carrier returns an acknowledgment with a claim reference number if the submission is accepted
5. Implement error handling for HTTP 4xx responses (validation failures): parse the error body to identify which fields failed validation and surface actionable messages to the broker
6. Store the carrier-assigned claim reference number in the BMS against the policy record; use it in subsequent CSIO API calls (e.g., Get Adjuster Details, Get Payment Status) to track the claim lifecycle