Purpose

Create and maintain financial tracking artifacts — ledgers, cashflow forecasts, debt schedules, budgets, and reconciliation reports — using double-entry bookkeeping principles. Every financial artifact must balance, state its assumptions, and maintain an audit trail.

When to use this skill

• The user asks to record transactions, maintain a ledger, or create journal entries.
• A task requires cashflow projection or a 13-week rolling forecast.
• The user needs debt tracking: amortization schedules, payoff comparisons (avalanche vs. snowball), or loan analysis.
• Budget-vs-actual variance analysis is requested.
• A repo contains financial tracking files (e.g.,

  finances/ledger.csv

  ,

  budget/2024-Q3.md

  ) that need updating or auditing.
• Account reconciliation is needed — matching ledger entries against bank statements or external records.

Do not use this skill when

• The task is market sizing, competitive analysis, or industry research — use

  market-research

  .
• The user wants to build pivot tables, clean CSV data, or perform spreadsheet transformations — use

  spreadsheet-analysis

  .
• The request is about investment portfolio optimization or securities analysis beyond basic position tracking.
• The user needs tax preparation or tax-code interpretation — flag as out-of-scope and recommend a qualified professional.
• The task is about building a financial software application — use coding-focused skills.

Operating procedure

Step 1 — Identify the financial artifact type

Determine which artifact the task requires:

Artifact	When to use	Key principle
Ledger entry	Recording a transaction	Double-entry: debits = credits
Cashflow forecast	Projecting future cash position	13-week rolling with weekly granularity
Debt schedule	Tracking loan repayment	Amortization with interest/principal split
Budget vs. actual	Comparing planned to real spending	Variance analysis with materiality threshold
Reconciliation	Matching two record sources	Every discrepancy must be classified

Step 2 — Apply double-entry bookkeeping principles

Every transaction must follow the fundamental accounting equation:

Assets = Liabilities + Equity

For every ledger entry:

1. Identify the accounts affected (at minimum two).
2. Determine which accounts are debited and which are credited.
3. Verify that total debits = total credits for the entry.
4. Classify each account: Asset, Liability, Equity, Revenue, or Expense.
5. Record date, description, reference number, and amounts.

Standard entry format:

Date: YYYY-MM-DD
Reference: [invoice/receipt/memo number]
Description: [what happened and why]
  Debit:  [Account Name]     $X,XXX.XX
  Credit: [Account Name]     $X,XXX.XX

If debits ≠ credits, the entry is rejected — do not proceed until balanced.

Step 3 — Cashflow projection (13-week rolling forecast)

Build the forecast with weekly granularity:

1. Opening balance: Start with confirmed bank balance as of the most recent reconciliation date.
2. Cash inflows: List expected receipts by week — categorize as Confirmed (contract/invoice), Probable (>75% likelihood), or Possible (<75%). Only Confirmed and Probable enter the base case.
3. Cash outflows: List committed payments (payroll, rent, loan payments, subscriptions) and discretionary spending by week.
4. Net cash flow: Inflows − Outflows per week.
5. Closing balance: Opening + Net cash flow = Closing. This week's closing = next week's opening.
6. Runway calculation: At current burn rate, how many weeks until cash reaches zero or minimum threshold?

Update the forecast weekly: move actuals into the historical column, extend the projection window by one week, and adjust estimates based on new information.

Step 4 — Debt tracking and payoff strategy

For each debt instrument, build an amortization schedule:

Payment #	Date	Payment	Principal	Interest	Remaining balance

Compare payoff strategies when multiple debts exist:

• Avalanche method: Pay minimums on all debts; direct extra payments to the highest-interest-rate debt first. Minimizes total interest paid.
• Snowball method: Pay minimums on all debts; direct extra payments to the smallest-balance debt first. Maximizes psychological momentum via quick wins.

Present both strategies with: total interest paid, total time to payoff, and monthly payment requirements. Recommend avalanche unless the user has explicitly stated a preference for snowball's behavioral benefits.

Step 5 — Budget vs. actual variance analysis

For each budget line item:

1. Record budgeted amount and actual amount.
2. Calculate variance (Actual − Budget) and variance % ((Actual − Budget) / Budget × 100).
3. Classify each variance:
   • Favorable: Actual spending below budget (expenses) or actual revenue above budget (income).
   • Unfavorable: The reverse.
4. Apply materiality threshold: Only investigate variances exceeding 5% AND $500 (or user-specified thresholds). Immaterial variances are noted but not analyzed.
5. For material variances, provide a root cause (price variance, volume variance, timing variance, or one-time event) and a corrective action if unfavorable.

Step 6 — Reconciliation

Match ledger entries against an external source (bank statement, invoice register, etc.):

1. Match confirmed items: Entries that appear in both records with matching dates and amounts.
2. Classify discrepancies:
   • Timing differences: Transaction recorded in one period in the ledger, another in the bank (e.g., outstanding checks). Expected to clear; no action needed beyond tracking.
   • Recording errors: Wrong amount, wrong account, duplicate entry. Requires correcting journal entry.
   • Unrecorded transactions: Bank fees, interest, or automatic payments not yet in the ledger. Requires new journal entries.
   • Unexplained differences: Cannot be classified. Escalate for investigation.
3. Reconciliation status: RECONCILED (all items matched or explained) or UNRECONCILED (unexplained differences remain; list them).

Decision rules

• Debits must equal credits. No exceptions. Reject any entry that doesn't balance.
• Never mix personal and business transactions in the same ledger or account. If encountered, flag immediately and recommend separation.
• Forecasts must state assumptions. Every cashflow projection number must trace to either a confirmed commitment or a stated assumption with a probability estimate.
• Use the most conservative reasonable estimate for cashflow forecasts: underestimate inflows, overestimate outflows. Optimistic forecasts that prove wrong cause more damage than conservative ones.
• Materiality thresholds are mandatory for variance analysis. Investigating every $5 variance wastes effort; define thresholds upfront.
• Reconciliation must happen before reporting. Never produce financial summaries from unreconciled ledgers. State reconciliation status prominently.
• Debt payoff recommendations default to avalanche unless the user explicitly requests snowball or states behavioral preference.

Output structure

Every financial deliverable must use the appropriate format:

Ledger Entry

## Journal Entry: [Reference #]
- Date: YYYY-MM-DD
- Description: [transaction description]
- Accounts:
  | Account          | Debit      | Credit     |
  |------------------|------------|------------|
  | [Account Name]   | $X,XXX.XX |            |
  | [Account Name]   |            | $X,XXX.XX |
- Balance check: Debits $X,XXX.XX = Credits $X,XXX.XX ✓
- Notes: [any additional context]

Cashflow Forecast

## 13-Week Cashflow Forecast (as of YYYY-MM-DD)
- Opening balance: $XX,XXX
- Assumptions: [list key assumptions]
- Forecast:
  | Week | Inflows | Outflows | Net | Closing Balance |
  |------|---------|----------|-----|-----------------|
- Runway: XX weeks at current burn rate
- Risk scenarios: [best case / base case / worst case closing balance at week 13]

Variance Report

## Budget vs. Actual: [Period]
- Materiality threshold: X% and $XXX
- Summary:
  | Category | Budget | Actual | Variance | Var % | Status |
  |----------|--------|--------|----------|-------|--------|
- Material variances requiring investigation:
  - [Category]: Root cause, corrective action
- Overall assessment: ON TRACK / CAUTION / OFF TRACK

Reconciliation Status

## Reconciliation: [Account] as of YYYY-MM-DD
- Ledger balance: $XX,XXX.XX
- External balance: $XX,XXX.XX
- Difference: $XX.XX
- Classified items:
  - Timing differences: $XX.XX (X items)
  - Recording errors: $XX.XX (X items — correcting entries attached)
  - Unrecorded transactions: $XX.XX (X items — new entries attached)
  - Unexplained: $XX.XX (X items — ESCALATE)
- Status: RECONCILED / UNRECONCILED

Anti-patterns

• Mixing personal and business finances: Commingling funds in a single ledger or account makes reconciliation unreliable and creates legal/tax exposure. Always separate.
• Unreconciled balances treated as accurate: Reporting from a ledger that hasn't been reconciled against bank statements. The numbers may be wrong. Reconcile first.
• Forecasts without stated assumptions: A cashflow projection that says "we'll receive $50K in Week 3" without stating whether that's confirmed revenue or an estimate. Every figure needs a basis.
• Single-entry bookkeeping: Recording only one side of a transaction (e.g., "paid $500 for supplies" without crediting the cash account). This breaks the accounting equation and makes error detection impossible.
• Ignoring materiality: Spending hours investigating a $12 variance while a $5,000 discrepancy sits unexamined. Set thresholds and enforce them.
• Snowball-by-default: Recommending the snowball method without disclosing that it costs more in total interest. Always present both options with total-cost comparison.

Related skills

• spreadsheet-analysis

  — Transforming raw financial CSV/Excel data into analysis-ready formats before ledger entry.

• market-research

  — Providing revenue assumptions and market context that feed into cashflow forecasts.

• business-idea-evaluation

  — Using financial projections as input to go/no-go business decisions.

• competitor-teardown

  — Analyzing competitor pricing and margin structures to inform budget assumptions.

Failure handling

• If the ledger doesn't balance, stop all downstream analysis (forecasts, variance reports) until the imbalance is resolved. Report the discrepancy amount and affected accounts.
• If reconciliation reveals unexplained differences exceeding the materiality threshold, escalate before producing any summary reports. Do not smooth over the gap.
• If the user provides incomplete transaction data (e.g., amount but no accounts), ask for the missing information rather than guessing. Incorrect account classification corrupts all downstream reporting.
• If the task requires tax advice, regulatory interpretation, or investment recommendations, state that this is outside the skill's scope and recommend consulting a qualified professional.