Korean Holiday CLI

Korean public holidays, business-day calculator, and lunar↔solar converter (CLI). Check if a date is a Korean public holiday (including 대체공휴일), list holidays...

Security Scan

The skill's code, docs, and runtime instructions are consistent with a local CLI for Korean holidays and lunar/solar conversion; it requests no credentials or unusual system access.

Purpose & Capability

Name/description match the included code and README: the script implements holiday checks, business-day math, and lunar↔solar conversion. No unrelated credentials, binaries, or services are requested.

Instruction Scope

SKILL.md instructs running the bundled Python script and installing two public Python packages. The runtime steps only parse dates, compute with local libraries, and emit JSON; there are no directives to read unrelated files, access secrets, or send data to external endpoints.

Install Mechanism

No explicit install spec is provided by the registry (instruction-only), but SKILL.md recommends pip install -r scripts/requirements.txt which will fetch dependencies from PyPI (holidays, korean-lunar-calendar). Using PyPI is normal but implies standard supply-chain risk when installing packages.

Credentials

The skill requires no environment variables, credentials, or config paths. The code only imports libraries and operates on dates; no sensitive data access is requested.

Persistence & Privilege

Skill does not request always:true, no modifications to other skills or system-wide settings, and is user-invocable. Autonomous invocation is allowed by default but not coupled with any broad privileges or credentials here.

Assessment

This skill is internally consistent and appears to do what it claims. Before installing/running: (1) install dependencies in an isolated environment (virtualenv/container) because pip will fetch packages from PyPI; (2) review the specific PyPI package versions if you require strict supply-chain controls; (3) note that runtime does not contact external services, but installing/updating packages does require network access to PyPI. If you need absolute offline operation, vendor the required packages or verify they are already present in your environment.

Korean Holiday & Business-Day CLI

Zero-config CLI for Korean public holidays, business-day math, and Korean lunar↔solar conversion. No API key. No network required at runtime.

• Public holidays powered by the holidays package (Korean names, substitute holidays / 대체공휴일 included).
• Lunar↔solar powered by korean-lunar-calendar (KASI astronomical tables, supports 윤달).

When to use

Trigger this skill for any of:

• Is a given date a Korean public holiday? ("2026-05-05 공휴일이야?")
• List Korean holidays for a year or month
• Compute next/previous business day, skipping weekends AND Korean holidays
• Add a signed business-day offset (e.g., invoice due in +10 business days from order date)
• Count business days between two dates (payroll, SLA, delivery ETA)
• Convert solar ↔ Korean lunar dates (음력 생일 lookup, 설날·추석 date lookup)
• Render a monthly calendar view with holidays marked

Do not use for:

• Regional / religious holidays that aren't recognized as national public holidays (예: 성탄절 제외 종교 행사)
• Company-specific working calendars (add your own per-company overrides outside this skill)
• Realtime election-day announcements (bundled rules reflect statutory holidays; ad-hoc presidential decree holidays may lag until the holidays package updates)

Install

pip install -r scripts/requirements.txt

Dependencies: holidays, korean-lunar-calendar.

Usage

All commands are sub-commands of scripts/kr_holiday.py. Output is JSON (UTF-8, Korean preserved). Dates accept YYYY-MM-DD, YYYYMMDD, YYYY/MM/DD, or YYYY.MM.DD.

Check a date

python scripts/kr_holiday.py is-holiday 2026-05-05
# → {"date":"2026-05-05","weekday":"Tue","is_weekend":false,"is_holiday":true,"is_business_day":false,"names":["어린이날"]}

List holidays in a year (optionally filter by month)

python scripts/kr_holiday.py list --year 2026
python scripts/kr_holiday.py list --year 2026 --month 5

Next / previous business day

python scripts/kr_holiday.py next-business-day 2026-05-02                 # skip Sat → 2026-05-04 (Mon)
python scripts/kr_holiday.py next-business-day 2026-05-02 --offset 3      # 3rd next business day
python scripts/kr_holiday.py prev-business-day 2026-05-06 --offset 2

Add a signed business-day offset

python scripts/kr_holiday.py add-business-days 2026-04-20 --days 10       # 2026-05-04
python scripts/kr_holiday.py add-business-days 2026-05-05 --days -3

Count business days in a range (inclusive)

python scripts/kr_holiday.py business-days --start 2026-05-01 --end 2026-05-31
# → {"start":"2026-05-01","end":"2026-05-31","calendar_days":31,"business_days":19}

Solar ↔ Korean lunar

python scripts/kr_holiday.py solar-to-lunar 2026-02-17
# → {"solar":"2026-02-17","lunar":"2026-01-01","is_leap_month":false,"gapja":"병오년 경인월 임술일"}

python scripts/kr_holiday.py lunar-to-solar 2026-08-15
python scripts/kr_holiday.py lunar-to-solar 2025-06-01 --leap              # pass --leap for 윤달

Monthly calendar view

python scripts/kr_holiday.py month 2026 5                   # human-readable, Sunday-first
python scripts/kr_holiday.py month 2026 5 --format json     # weeks grid in JSON

Output conventions

• JSON by default (no pretty-print; pipe through python -m json.tool if desired).
• is_business_day = true ⇔ Mon–Fri AND not a Korean public holiday.
• names is a list — a single calendar day can carry multiple labels (e.g., when holidays overlap).
• Substitute holidays (대체공휴일) appear as their own entries in list output.

Error handling

• Unparseable date → exit 2, stderr JSON {"error":"bad_date","input":"…"}.
• Out-of-range month, negative offset, conversion failure → exit 2 or 3, stderr JSON.
• Missing dependency → exit 4, stderr JSON with install hint.

Notes on holiday accuracy

• 대체공휴일 rules: reflects the revised 2021/2023 rules (substitute applies when a national holiday falls on Sat/Sun, with the documented exceptions). Results match rulings published by 공공데이터포털 한국천문연구원 특일 정보 through 2030.
• Lunar holidays (설날, 추석, 부처님오신날) are computed from the lunar calendar bundled in the holidays package.
• Update holidays periodically to pick up legislative changes: pip install -U holidays.

See also

• krx-stock-cli — KRX stock market data (KOSPI/KOSDAQ)
• toss-payments-cli — Toss Payments API
• kakao-local-cli — Kakao Local place & geocoding API

License

MIT.