Atlas / Skills / jeremylongshore / Calculating Crypto Taxes

Calculating Crypto TaxesSAFE

skills/jeremylongshore/calculating-crypto-taxes

Model-agnostic agent-skills platform with a harness-free canonical layer, verified adapters, and the ccpi package manager. Explore at tonsofskills.com.

Verdict
SAFE
Grade
B
Trust score
89 /100
Version
1.27.0
Hosts
1 documented
License
MIT
Stars
2,823
01

Overview

Model-agnostic agent-skills platform with a harness-free canonical layer, verified adapters, and the ccpi package manager. Explore at tonsofskills.com.

Read from source at commit 4f83675ca38aOBSERVED · 2026-10-08
02

Host compatibility

What the documentation claims. We have not run a compatibility test.

HostStatusNotes
claude-codementioned
03

What it tells the agent

The instruction file, verbatim from the audited commit — this is the text the model reads, and the surface the audit's instruction layer examines. Quoted here so you can judge it without cloning anything.

---
name: calculating-crypto-taxes
description: 'Calculate cryptocurrency tax obligations with cost basis tracking, capital
  gains computation, and Form 8949 generation.

  Use when calculating crypto taxes, generating tax reports, comparing cost basis
  methods, or identifying taxable events.

  Trigger with phrases like "calculate crypto taxes", "generate tax report", "cost
  basis FIFO", "capital gains", "Form 8949", or "crypto taxable events".

  '
allowed-tools: Read, Write, Bash(crypto:tax-*)
version: 1.27.0
author: Jeremy Longshore <[email protected]>
license: MIT
tags:
- crypto
- cost-optimization
- calculating-crypto
compatibility: Designed for Claude Code
---
# Calculating Crypto Taxes

## Overview

Calculate cryptocurrency tax obligations from transaction history. Supports FIFO, LIFO, and HIFO cost basis methods, identifies taxable events (trades, staking, airdrops), and generates Form 8949 compatible reports.

**DISCLAIMER**: This tool provides informational calculations only, not tax advice. Consult a qualified tax professional.

## Prerequisites

- Transaction history exported as CSV from your exchanges (Coinbase, Binance, Kraken, etc.)
- Python 3.8+ installed
- Understanding of your tax jurisdiction's crypto rules

## Instructions

1. **Prepare transaction data** by exporting CSV from each exchange:

   | Exchange | Export Location |
   |----------|-----------------|
   | Coinbase | Reports > Tax documents > Transaction history CSV |
   | Binance | Orders > Trade History > Export |
   | Kraken | History > Export |
   | Generic | See `${CLAUDE_SKILL_DIR}/references/exchange_formats.md` for column mapping |

2. **Run basic tax calculation** using FIFO (IRS default):

   ```bash
   python ${CLAUDE_SKILL_DIR}/scripts/tax_calculator.py --transactions your_trades.csv --year 2025  # 2025 = tax year
   ```

3. **Compare cost basis methods** to understand tax implications:

   ```bash
   python ${CLAUDE_SKILL_DIR}/scripts/tax_calculator.py --transactions trades.csv --compare-methods
   ```

   Methods: `--method fifo` (IRS default), `--method lifo` (Last In First Out), `--method hifo` (minimize gains)

4. **Generate Form 8949 report** as CSV:

   ```bash
   python ${CLAUDE_SKILL_DIR}/scripts/tax_calculator.py --transactions trades.csv --method fifo --year 2025 --output form_8949.csv --format csv  # 2025 = tax year
   ```

5. **Handle income events** (staking, airdrops, mining, DeFi yield):

   ```bash
   python ${CLAUDE_SKILL_DIR}/scripts/tax_calculator.py --transactions all_events.csv --income-report
   ```

6. **Consolidate multi-exchange data** into a unified report:

   ```bash
   python ${CLAUDE_SKILL_DIR}/scripts/tax_calculator.py --transactions coinbase.csv binance.csv kraken.csv --year 2025  # 2025 = tax year
   ```

## Output

Reports include short-term and long-term capital gains/losses broken down by transaction, with proceeds, cost basis, and gain/loss per disposal. Summary shows total proceeds, total cost basis, net capital gain, and short/long-term split. Income report lists staking, airdrop, and mining income with fair market values.

See `${CLAUDE_SKILL_DIR}/references/implementation.md` for detailed output format examples.

## Error Handling

| Error | Cause | Fix |
|-------|-------|-----|
| Missing columns | CSV format mismatch | Verify format matches exchange template |
| Unknown transaction type | Unrecognized event category | Review and manually categorize |
| Insufficient lots | Missing buy transactions | Check for missing imports or transfers |

## Examples

**Basic FIFO tax calculation** - Standard IRS-default method for a single exchange:

```bash
python tax_calculator.py --transactions trades.csv --year 2025  # 2025 = tax year
```

**HIFO to minimize gains** - Highest-cost lots disposed first to reduce taxable gain:

```bash
python tax_calculator.py --transactions trades.csv --method hifo --year 2025  # 2025 = tax year
```

**JSON output for processing** - Machine-readable export for tax software integration:

```bash
python tax_calculator.py --transactions trades.csv --format json --output tax_data.json
```

**Verbose with lot details** - See which specific lots were matched to each disposal:

```bash
python tax_calculator.py --transactions trades.csv --verbose --show-lots
```

## Resources

- IRS Virtual Currency Guidance: https://www.irs.gov/businesses/small-businesses-self-employed/virtual-currencies
- Form 8949 Instructions: https://www.irs.gov/instructions/i8949
- CoinGecko API for historical prices
- `${CLAUDE_SKILL_DIR}/references/implementation.md` - Detailed output formats, configuration, advanced usage
04

Trust audit

SAFEgrade B · trust 89/100 Nothing in the source contradicts what it says it does. Grade A is reserved for packages that have also passed the behavioural sandbox.

LayerWhat it checksResult
L0Provenance & inventoryPASS
L1Static analysis of the codePASS
L2Instruction surface (what it tells the agent)PASS
L3Class-specific surfacePASS
L4Behavioural (sandbox)SKIPPED

What the source does

Filesystem
none-observed
Network
none-observed
Shell
none-observed
Dependencies
pinned
Secrets in source
none-found

Findings (0)

No findings outside the package's declared scope.

Gates applied: no_behavioural_pass.

Audited 2026-10-08 · audit v0.4.1 · source sha 4f83675ca38afull audit observations/trust-audit/skill/jeremylongshore__calculating-crypto-taxes.json · Report an issue / request a re-scan
05

Audit history

Every audit this skill has had.

DateSourceVerdictGradeScoreChange
2026-10-084f83675ca38aSAFEB89first audit
06

Questions

What does the Calculating Crypto Taxes skill do?

Model-agnostic agent-skills platform with a harness-free canonical layer, verified adapters, and the ccpi package manager. Explore at tonsofskills.com.

Is Calculating Crypto Taxes safe to install?

The audit found nothing in the source that contradicts what it says it does, and graded it B (89/100). Grade A is held back for packages that have also passed a sandboxed behavioural run, which is why a clean skill reads B.

What can Calculating Crypto Taxes access on my machine?

The audit observed no filesystem, network or shell use at all in its source.

Which assistants does Calculating Crypto Taxes work with?

Its documentation mentions claude-code. That is what the text claims, not a compatibility test we ran.

How current is this page?

The grade is for one exact copy of the source (4f83675ca38a), read on 2026-10-08. The repository is watched, and a new audit runs when it changes — this is the first audit.

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