Process X12 834 benefit enrollment files

Verified steps

1. Establish an EDI trading partner agreement with the employer or benefits administrator sending the 834; agree on the implementation guide version (HIPAA-mandated version is 005010X220A1 for group health) and agree on transmission method (AS2, SFTP, or VAN).
2. Receive the 834 file and validate the three envelope layers: Interchange Control (ISA/IEA), Functional Group (GS/GE), and Transaction Set (ST/SE); reject malformed files with a TA1 interchange acknowledgment and a 999 functional acknowledgment indicating the error segment.
3. Parse the hierarchical loops: Loop 1000A (sponsor), Loop 1000B (payer), Loop 2000 (member), Loop 2100 (member name/address), Loop 2300 (health coverage), and Loop 2700 (member reporting category); extract INS01 maintenance type code to determine if the record is an add, change, or termination.
4. Apply business rules to the parsed records: validate SSN, verify eligibility dates are within the group contract period, check for duplicate member IDs, and confirm coverage type codes are valid for the group's benefit plan.
5. Load approved enrollment records into the membership/enrollment system; trigger downstream processes for ID card generation, billing group update, and provider directory notification.
6. Return a 999 Implementation Acknowledgment to the sender confirming accepted/rejected transaction sets; for rejected records, include the error segment ID and error code so the sender can correct and resubmit.