Upstage Inc. said the National Tax Service will route a slice of Chuseok helpline overflow through Solar Pro, its Korean-language large-language triage stack, after NTS forecast a surge in inheritance, gift-tax, and year-end filing questions as families gather for ancestral rites. The system summarizes caller intent and suggests official FAQ paths for human agents; it does not file returns or compute liability on its own, preserving Hometax as the sole submission channel.
Why Chuseok spikes call volume
Holiday reunions surface conversations about transferring assets, cash gifts to children, and reporting overseas accounts that younger relatives manage for parents. NTS historically staffs extra phones through September filing season, but Chuseok compresses demand into a few evenings when offices are closed yet family lawyers are reachable by phone. Last year’s average wait times exceeded twenty minutes on peak outbound travel days; NTS published shorter waits as a service goal this cycle.
Solar Pro listens to transcribed audio—not live open microphones stored indefinitely—and returns agent-facing bullet points citing relevant NTS notice numbers when confidence scores clear thresholds.
Solar Pro triage design
Upstage fine-tuned Solar Pro on anonymized historical call logs and public tax guidance, with human reviewers labeling intent categories like gift reporting thresholds, funeral expense deductions, and cryptocurrency disclosure FAQs. The model abstains when confidence is low, forcing warm transfer to senior agents rather than guessing on legally sensitive topics.
Agents see a sidebar with suggested script paragraphs they can edit before speaking; all customer-facing wording remains human-approved to meet Personal Information Protection Commission expectations on automated advice.
Privacy and data handling
Call audio is processed in Korean sovereign cloud regions under NTS contracts; retention deletes triage intermediates within seventy-two hours unless a dispute file requires longer storage. Upstage said no taxpayer identifiers train foundation weights; continuous learning uses aggregated intent statistics only.
Privacy advocates asked whether LLM summaries could leak across concurrent calls; NTS isolation tests reported no cross-session bleed in August pilots.
Agent workflow
Level-one agents handle password resets and portal navigation; Solar Pro elevates complex inheritance questions to specialists with pre-filled context, shaving minute-per-call handle time in trials. Supervisors monitor random samples for hallucinated statute citations—a zero-tolerance QA rule that triggered two model downgrades during summer testing.
English-language callers still route to dedicated desks; Solar Pro triage is Korean-first this holiday, with English roadmap items for next filing season.
Limits of automation
Upstage and NTS repeated in joint notices that AI summaries are not binding rulings; written preliminary answers require official NTS inquiry channels. Promotional crypto schemes and third-party “tax refund” scams spike during Chuseok; triage scripts flag keywords linked to Financial Supervisory Service fraud alerts and refer callers away from Solar Pro to fraud hotlines.
Taxpayers should not read social media posts claiming Solar Pro approves deductions; only Hometax submissions count.
Broader AI procurement
The pilot fits Ministry of Economy and Finance digitization budgets that favor Korean AI vendors for sensitive workloads. Competitors Naver HyperCLOVA and KT models bid on adjacent chatbot slots; Upstage won the helpline slice on accuracy benchmarks on gift-tax utterances, according to procurement summaries NTS posted in redacted form.
If handle times drop without complaint upticks, NTS may expand Solar Pro to VAT helplines after Chuseok; failure would revert to legacy IVR trees without public model blame games.
Taxpayer practical tips
Callers should have identification and case numbers ready, avoid sharing full account passwords aloud, and use Hometax mobile for status checks before phoning. Families discussing gifts should record amounts and dates to match FAQ thresholds agents will cite.
Upstage engineers stay on-call through the holiday weekend for model rollback if error rates spike—a contingency NTS insisted upon before go-live.
Success metrics
NTS will judge the deployment on average wait, first-contact resolution, and complaint rates to the taxpayer advocate office—not on flashy automation percentages. For Upstage, a quiet Chuseok on the phones is the best proof that Korean LLMs can assist public servants without crossing into unsupervised tax advice.