home / skills / phrazzld / claude-config / tax-check

tax-check skill

safe

/skills/tax-check

This skill validates tax calculations and surfaces audit risks by reconciling brackets, deductions, and Form 8949 formats for accurate reporting.

npx playbooks add skill phrazzld/claude-config --skill tax-check

Review the files below or copy the command above to add this skill to your agents.

Files (1)

SKILL.md

1003 B

---
name: tax-check
description: |
  Validate tax calculations: bracket math, deduction eligibility, Form 8949 format, audit-risk flags.
user-invocable: true
effort: high
---

# /tax-check

Validate tax calculations and surface risks.

## Steps

1. Rebuild reports to ensure fresh numbers.
2. Verify bracket math against configured year constants.
3. Recompute taxable income: wages + gains - deductions, confirm totals.
4. Validate Form 8949 CSV format and totals vs `normalized/capital-gains.json`.
5. Flag audit risks: large losses, missing basis, inconsistent dates, or missing source docs.

## Examples

```bash
# Regenerate tax outputs before validation
pnpm report
```

```bash
# Rebuild gains if source data changed
pnpm gains
```

## References

- `scripts/generate-report.ts`
- `normalized/capital-gains.json`
- `normalized/w2-data.json`
- `normalized/charitable-donations.json`
- `reports/2025-tax-summary.md`
- `reports/tax-ready/form-8949-c.csv`
- `reports/tax-ready/schedule-d-summary.md`

Overview

This skill validates tax calculations and surfaces potential audit risks across income, gains, and deductions. It checks bracket math, recomputes taxable income, inspects Form 8949 formatting, and flags anomalies that warrant review. The goal is to catch calculation errors and documentation gaps before filing.

How this skill works

The skill rebuilds tax reports to use fresh numbers and then verifies bracket calculations against configured year constants. It recomputes taxable income from wages, gains, and deductions and compares totals to source-normalized data. It also validates Form 8949 CSV format and totals against normalized capital gains records and generates audit-risk flags for large losses, missing basis, inconsistent dates, or absent source documents.

When to use it

Before finalizing or filing a tax return to ensure calculations are correct.
After updating source data such as W-2s, gains, or donation records.
When preparing Form 8949 or Schedule D to confirm CSV formatting and totals.
During a pre-audit review to identify items likely to draw IRS attention.
When integrating new tax-year constants or bracket changes.

Best practices

Regenerate reports first so validations run against the latest computed numbers.
Keep normalized source files (wages, capital gains, donations) current and auditable.
Compare recomputed totals to both summary reports and raw normalized records.
Treat audit-risk flags as prompts for documentation rather than definitive errors.
Review and document any large losses, missing basis entries, or date mismatches promptly.

Example use cases

Run the validation after running report generation to confirm bracket math and taxable income totals.
Validate a newly produced Form 8949 CSV against normalized capital gains to catch formatting or subtotal mismatches.
Scan a client’s tax dataset for audit-risk items like missing basis or inconsistent trade dates.
Re-run checks after importing updated W-2 or donation data to ensure deductions and wages reconcile.
Use the flags to assemble supporting documents before submission or to respond to a notice.

FAQ

Does this skill change tax data or only report issues?

It only validates and reports discrepancies; it does not modify source data automatically.

What triggers an audit-risk flag?

Flags arise from large losses, missing cost basis, inconsistent transaction dates, or absent supporting documents.

Can I run validations for a specific tax year?

Yes. The checks use configured year constants for bracket math and should be run against the corresponding normalized data.