assess

Determination of Filing Requirement and Type (Tax Filing Assessment)

A skill that interactively determines whether a tax return (確定申告) is required and what type of filing is needed. It interviews the user about their income situation, family structure, and business situation, and identifies the required filings.

Loading settings (execute first)

shinkoku.config.yaml Read with the Read tool
If the file does not exist, /setup guide the user to run the skill and exit
Understand the setting values, and convert relative paths to absolute paths based on CWD:
- db_path: Used for the CLI script's --db-path argument
- output_dir: Base directory for output such as progress files
- Each directory: Used when referencing files

Loading progress information

After loading the settings, read the handover file to understand the results of the previous step.

.shinkoku/progress/progress-summary.md Read with the Read tool (if it exists)
Read the following handover file with the Read tool (if it exists):
- .shinkoku/progress/01-setup.md
Use the loaded information in subsequent steps (avoid re-asking the user)
If the file does not exist, skip it and confirm the necessary information directly with the user

Basic policy for determination

When the user speaks in terms of "income" (収入), internally convert it to "income" (所得) and make the determination
Perform the determination in the order: income tax → consumption tax → resident tax
Show the statutory provisions and administrative notices that form the basis for each determination
Present the determination results as a summary list at the end
If there are unclear points, confirm them with additional questions (do not make determinations based on guesswork)

Rules for designing questions during the interview

Checklist items mustall be confirmed without omission. Do not omit items due to the tool's option count limit (AskUserQuestion allows a maximum of 4 options per question). If there are many items,split into multiple roundsand confirm
If a single event has multiple aspects (e.g., purchasing a used home and also doing renovations), make it **multiple-selectable (multiSelect: true)** or include combination patterns in the options
Before designing the options, determine whether that item isexclusive (choose only one) or parallel (multiple may apply)determine

Step 1: Basic information interview

Collect the following information through dialogue. Do not ask everything at once; confirm gradually in a natural conversational flow.

1-0. Confirmation of last year's tax return

If there is business income (from the second year after starting the business onward), confirm the contents of last year's tax return. If there is a file in config's past_returns_dir , refer to it.

Confirmation items

Whether there was a prior-year final tax return (Form B/First Table)
Prior-year business income amount (profit or loss)
Prior-year income tax due (line ㊺) — whether it exceeded 150,000 yen
Whether there was prepayment of tax and the amount already paid (1st period/2nd period)
Whether there is a net loss carryover deduction (whether a blue return loss was reported in a prior year or earlier)
Prior-year consumption tax taxable sales (used to determine the base period)

Rules for determining prepayment of tax (Income Tax Act Article 104)

If the prior-year income tax due (line ㊺) is 150,000 yen or more then:

1st period (July): 1/3 of the prior-year tax due
2nd period (November): 1/3 of the prior-year tax due
The remainder is settled in the final tax return

If prepayment of tax has been paid, add it to line ㊹ "Income tax withheld" on the final tax return.

Net loss carryover deduction (Income Tax Act Article 70)

If there is a net loss from a blue return within the 3 years before the prior year:

Check the amount eligible for carryover deduction
It can be deducted from the current year's income

1-1. Confirmation of salary income

Whether there is salary income and the approximate amount
Number of salary payers (one or multiple)
Whether year-end adjustment was performed
Whether there is a withholding tax slip

1-2. Confirmation of income other than salary

Check whether the following income exists,allin order (if there are many items, split into multiple rounds):

Business income (side job/freelance) → approximate amount, whether a business commencement notification was filed, whether blue return approval was obtained
Real estate income
Stock/dividend income (specified account/general account/NISA) → confirm details in 1-2a
Miscellaneous income (crypto assets, FX, pensions, etc.) → confirm details in 1-2b, 1-2c
Temporary income (insurance maturity proceeds, prize money, etc.)
Transfer income (sale of real estate, golf membership, etc.)
Retirement income

1-2a. Detailed confirmation of stock transactions (only for those applicable)

If there is stock/dividend income, confirm the following:

Type of account:
- Specified account (with withholding): filing a final tax return is optional. However, filing is required for loss offset and carryover losses
- Specified account (without withholding): filing a final tax return is required
- General account: filing a final tax return is required
- NISA account: tax-exempt. No filing required
Selection of dividend taxation method:
- Comprehensive taxation: the dividend deduction can be used (often advantageous if taxable income is 6.95 million yen or less)
- Separate taxation: loss offset with stock transfer losses is possible
- No filing required: can be selected only for a specified account (with withholding)
Confirmation of loss offset:
- Stock transfer losses and dividends for which separate taxation is selected can be offset
- Whether prior-year or earlier carryover losses (up to 3 years) can be applied
Estimated amount: Annual capital gains/losses, dividend amount, income tax withheld

1-2b. Detailed confirmation of FX transactions (only for those applicable)

If there are FX transactions, confirm the following:

Type of transaction: Over-the-counter FX / exchange-traded FX (both are separate taxation)
Annual profit/loss: Realized profit/loss + swap income - transaction fees, etc.
Carryover loss: Whether there is a carryover loss from prior years or earlier (up to 3 years)
Note: FX profit/loss cannot be offset against stocks (separate pool)

1-2c. Detailed confirmation of virtual currency (crypto assets) (only for those applicable)

If there are crypto asset transactions, confirm the following:

Type of transaction: Sale, exchange, use for payment, mining, etc.
Annual profit/loss: Calculated using the total average method or moving average method
Taxation category: Declared as miscellaneous income (comprehensive taxation)
Note: Crypto asset losses cannot be offset against other income (only offsettable within miscellaneous income)

1-3. Confirmation related to deductions

Confirm the following itemsallConfirm. Since there are many items, confirm in two rounds.

Group A: Large deductions (items directly linked to whether a tax return is required)

Housing loan deduction (first year or second year onward) ★Affects whether filing is required
Payment of medical expenses (guideline: over 100,000 yen)
Presence and amount of furusato nozei (usage status of the one-stop special exception)

Group B: Other deductions

Enrollment in iDeCo / small enterprise mutual aid
Enrollment in life insurance / earthquake insurance
Presence of dependents

1-4. Detailed confirmation of home acquisition (if the housing loan deduction applies)

If acquisition or renovation of a home is identified, additionally confirm the following.

Type of acquisition (multiple may apply, so confirm with multiSelect)

Acquisition of a newly built home
Acquisition of a used home (existing home)
Extension/renovation or remodeling

※“Purchasing a used home and also doing renovation” is a common pattern, so be sure to allow multiple selections. In the case of used home acquisition + renovation, the borrowing limit for the housing loan deduction may differ for each.

Detailed information to confirm

Acquisition price (if the breakdown of land/building is known)
Renovation cost (if applicable)
Presence of a housing loan and estimated year-end balance
Move-in date (whether moved in within 6 months after acquisition)
Floor area (whether 50 m² or more; if income is 10 million yen or less, 40 m² or more)
If used: Construction year (Showa 57/1982 or later = new earthquake resistance standard)
Energy-saving performance category (certified long-term excellent housing, ZEH, energy-saving standard compliant, other)

→ To determine the detailed deduction amount, run /tax-housing-loan-context

Hearing completion checklist

Before proceeding to the Step 2 determination, all of the following must have been confirmed. If any item remains unconfirmed, ask the user additional questions.

Income-related

Presence/absence, amount, and number of payers of salary income
Whether year-end adjustment was performed
Presence/absence of business income (side job/freelance)
Presence/absence of real estate income
Presence/absence of stock/dividend income
Presence/absence of miscellaneous income (crypto assets, FX, pensions, etc.)
Presence/absence of temporary income
Presence/absence of transfer income
Presence/absence of retirement income

Deduction-related

Whether the housing loan deduction applies (first year or second year onward)
Status of medical expense payments
Presence/absence of hometown tax donations
Whether enrolled in iDeCo/small enterprise mutual aid
Whether enrolled in life insurance/earthquake insurance
Presence/absence of dependents

Previous year's tax return-related

Previous year's declared tax amount (determination of whether estimated tax payment is necessary)
Presence/absence of estimated tax payment and amount already paid
Presence/absence of net loss carryforward

Step 2: Determination of whether an income tax return is required

Based on the collected information, determine using the following flowchart.

Determination flowchart: Cases where a tax return is required

Q1. 給与所得者ですか？
├── Yes → Q2へ
└── No → Q5へ

Q2. 給与収入は2,000万円を超えますか？
├── Yes → 【確定申告必要】（所得税法第121条第1項）
└── No → Q3へ

Q3. 給与を2か所以上から受けていますか？
├── Yes → 主たる給与以外の収入が20万円を超えるか確認 → Q4へ
└── No → Q4へ

Q4. 給与所得・退職所得以外の所得が20万円を超えますか？
├── Yes → 【確定申告必要】（所得税法第121条第1項第2号）
└── No → Q6へ

Q5. 事業所得・不動産所得等がありますか？
├── Yes → 所得金額が基礎控除+所得控除の合計を超えるか？
│   ├── Yes → 【確定申告必要】
│   └── No → 【確定申告不要】（ただし損失繰越のために申告する場合あり）
└── No → 各所得の合計で判定

Q6. 以下のいずれかに該当しますか？
- 医療費控除を受けたい
- ふるさと納税でワンストップ特例を使わない/使えない
- 住宅ローン控除の初年度
- 雑損控除を受けたい
- 年末調整で申告漏れした控除がある
├── Yes → 【確定申告した方が有利（還付申告）】
└── No → 【確定申告不要】

Cases where a tax return is not required (confirmatory presentation)

If any of the following apply, clearly state that a tax return is not required:

A salaried worker who has completed year-end adjustment and whose side job income is 200,000 yen or less (however, a resident tax return is required)
Public pension, etc. income is 4 million yen or less and income other than pension is 200,000 yen or less
Income is equal to or less than the basic deduction amount

Note: Cases where a tax return is required even if income is 200,000 yen or less

Even if side job income is 200,000 yen or less and an income tax return is not required, a tax return is required in the following cases:

A resident tax return is separately required (filed with the municipality)
If filing a tax return to claim the medical expense deduction, etc., income of 200,000 yen or less must also be included
The one-stop special exception for hometown tax donations becomes invalid if a tax return is filed

Step 2.5: (Out of scope) Determination of whether a separate taxation return is required

Calculation and form generation for separate taxation (stocks/FX third schedule) are out of scope. If there are stock transactions or FX transactions, guide the user to consult a tax accountant. Virtual currency is handled in the income tax skill as miscellaneous income (comprehensive taxation).

Step 3: Determination of whether a consumption tax return is required

Decision flowchart: Consumption tax taxable business operator determination

Q1. 事業収入（売上）がありますか？
├── No → 【消費税申告不要】
└── Yes → Q2へ

Q2. 基準期間（2年前: 令和5年）の課税売上高が1,000万円を超えますか？
├── Yes → 【課税事業者】→ 消費税申告必要
└── No → Q3へ

Q3. 特定期間（前年1-6月: 令和6年1-6月）の課税売上高または
    給与支払額が1,000万円を超えますか？
├── Yes → 【課税事業者】→ 消費税申告必要
└── No → Q4へ

Q4. 適格請求書発行事業者（インボイス登録）をしていますか？
├── Yes → 【課税事業者（インボイス登録による）】→ 消費税申告必要
│         → 2割特例の適用可否を確認（令和8年9月30日までの経過措置）
└── No → 【免税事業者】→ 消費税申告不要

Determination of consumption tax filing method

If determined to be a taxable business operator, determine the following filing method:

Q1. 2割特例の適用要件を満たすか？
    （インボイス登録により課税事業者になった者で、基準期間の課税売上が1,000万円以下）
├── Yes → 2割特例が最も有利な場合が多い。簡易課税・本則課税との比較を提案
└── No → Q2へ

Q2. 基準期間の課税売上高が5,000万円以下で、簡易課税の届出をしているか？
├── Yes → 簡易課税で申告
└── No → 本則課税で申告

Step 4: Determination of whether resident tax filing is required

Decision flowchart

Q1. 確定申告を行いますか？
├── Yes → 住民税の申告は不要（確定申告データが市区町村に送付される）
└── No → Q2へ

Q2. 給与所得のみで年末調整済みですか？
├── Yes → Q3へ
└── No → 【住民税の申告が必要】

Q3. 給与以外の所得がありますか？（20万円以下を含む）
├── Yes → 【住民税の申告が必要】（所得税では不要でも住民税は必要）
└── No → 住民税の申告は不要（給与支払報告書が提出されている）

Confirmation of resident tax collection method

For salaried employees with side income, confirm the following:

Ordinary collection (self-payment): If you do not want your side income to be known by your company
Special collection (payroll withholding): Default
Selectable in the "Matters concerning resident tax" section of the final tax return

Step 5: Presentation of determination result summary

Once all determinations are complete, summarize and present the results in the following format:

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
申告要否・種類の判定結果
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

■ 所得税の確定申告: [必要 / 不要 / 還付申告推奨]
  根拠: [該当条文・理由]

■ 分離課税: 対象外（該当する場合は税理士への相談を案内）

■ 消費税の申告: [必要 / 不要]
  課税事業者区分: [課税事業者 / 免税事業者]
  申告方法: [2割特例 / 簡易課税 / 本則課税]

■ 住民税の申告: [不要（確定申告で対応） / 別途必要]

■ shinkoku 対応状況:
  対応レベル: [Full / Partial / Out]
  [Partial/Out の場合: 未対応の項目と対応方法を記載]

■ 次のステップ:
  → gather スキルで必要書類を確認する
  → [その他の推奨アクション]
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Output of handover document

After presenting the summary, output the following file using the Write tool. This allows the results to be carried over to the next step even if the session is interrupted or Compact occurs.

Output of step-specific files

.shinkoku/progress/02-assess.md Output to in the following format:

---
step: 2
skill: assess
status: completed
completed_at: "{当日日付 YYYY-MM-DD}"
fiscal_year: {tax_year}
---

# 申告要否・種類の判定結果

## 判定結果

- 所得税の確定申告: {必要/不要/還付申告推奨}（{根拠}）
- 消費税の申告: {必要/不要}
- 住民税の申告: {不要（確定申告で対応）/別途必要}
- 青色申告特別控除: {65万円/10万円}（{根拠}）

## 収入の概要

- 給与収入: {あり/なし}（{詳細}）
- 事業収入: {あり/なし}（{詳細}）
- 株式取引: {あり/なし}（{口座種類、概算損益}）
- FX取引: {あり/なし}（{概算損益}）
- 仮想通貨: {あり/なし}（{概算損益}）
- 雑所得: {あり/なし}（{詳細}）
- 配当所得: {あり/なし}（{課税方式: 総合/分離/申告不要}）
- 一時所得: {あり/なし}（{詳細}）
- その他の収入: {該当する収入があれば記載}

## 分離課税

- 対象外（該当する場合は税理士への相談を案内済み）

## 予定納税

- 前年の申告納税額（㊺欄）: {金額}円
- 予定納税額: {金額}円（第1期・第2期 各{金額}円、{納付済み/未納付}）

## 純損失の繰越控除

- 繰越控除の有無: {あり/なし}
- 繰越損失額: {金額}円（{損失発生年度}）

## 消費税の詳細

- 課税事業者区分: {課税事業者/免税事業者}（{根拠}）
- 基準期間の課税売上高: {金額}万円
- 適用可能な方法: {2割特例/簡易課税/本則課税}

## 次のステップ

/gather で必要書類を確認する

Update of progress summary

.shinkoku/progress/progress-summary.md Update (create new if it does not exist):

YAML frontmatter: fiscal_year, last_updated (current date), current_step: assess
Table: Update the status of all steps (set assess to completed)
Describe guidance for the next step

Guidance after output

After outputting the file, tell the user the following:

"I saved the handover document to .shinkoku/progress/ . Even if the session is interrupted, the results can be carried over in the next skill."
Guidance for the next step

Handling of special cases

If you retired partway through the year

Year-end adjustment not performed → Settlement required via final tax return
If there is a retirement allowance → Check the withholding slip for retirement income

Overseas-related

Clearly state that overseas residents (non-residents) are not covered
Confirm the applicability of the foreign tax credit

Special provisions for disasters, etc.

Confirm the applicability of the casualty loss deduction and the Disaster Relief Act due to disaster

Additional Resources

Reference Files

For detailed determination logic, refer to the steps above.

Presentation of disclaimer

When presenting the determination results, always add the following:

This determination is based on general criteria and may differ depending on individual circumstances
It is recommended to confirm the final decision with a tax accountant or other professional
The following income categories are not currently supported, so if applicable, guide the user to consult a tax accountant:
- Capital gains (e.g., sale of real estate) — No calculation for long-term/short-term tax rates or the 30 million yen special deduction
- Foreign tax credit — no tracking of foreign tax payments or credit calculation
- Agricultural income / forest income — no dedicated income categories or special calculations
- Non-residents — only Japanese residents are covered
If a disclaimer needs to be added, run /tax-legal-context