tracking-crypto-prices

What this skill does

# Tracking Crypto Prices

## Contents

[Overview](#overview) | [Prerequisites](#prerequisites) | [Instructions](#instructions) | [Output](#output) | [Error Handling](#error-handling) | [Examples](#examples) | [Resources](#resources)

## Overview

Foundation skill providing real-time and historical cryptocurrency price data for 10,000+ coins. This is the data layer for the crypto plugin ecosystem -- 10+ other skills depend on it for price information.

## Prerequisites

1. Install dependencies: `pip install requests pandas yfinance`
2. Optional: `pip install python-dotenv` for API key management
3. Optional: Get free API key from https://www.coingecko.com/en/api for higher rate limits
4. Add API key to `${CLAUDE_SKILL_DIR}/config/settings.yaml` or set `COINGECKO_API_KEY` env var

## Instructions

1. Check current prices for one or more symbols:

   ```bash
   python ${CLAUDE_SKILL_DIR}/scripts/price_tracker.py --symbol BTC
   python ${CLAUDE_SKILL_DIR}/scripts/price_tracker.py --symbols BTC,ETH,SOL
   ```

2. Use watchlists to scan predefined groups (available: `top10`, `defi`, `layer2`, `stablecoins`, `memecoins`):

   ```bash
   python ${CLAUDE_SKILL_DIR}/scripts/price_tracker.py --watchlist top10     # Top 10 by market cap
   python ${CLAUDE_SKILL_DIR}/scripts/price_tracker.py --watchlist defi      # DeFi tokens
   python ${CLAUDE_SKILL_DIR}/scripts/price_tracker.py --watchlist layer2    # Layer 2 tokens
   ```

3. Fetch historical data by period or custom date range:

   ```bash
   python ${CLAUDE_SKILL_DIR}/scripts/price_tracker.py --symbol BTC --period 30d
   python ${CLAUDE_SKILL_DIR}/scripts/price_tracker.py --symbol BTC --period 90d --output csv
   python ${CLAUDE_SKILL_DIR}/scripts/price_tracker.py --symbol ETH --start 2024-01-01 --end 2024-12-31  # 2024 full year
   ```

4. Configure settings by editing `${CLAUDE_SKILL_DIR}/config/settings.yaml` to customize cache TTLs, default currency, and custom watchlists. See `references/implementation.md` for the full configuration reference.

## Output

- **Table** (default): Symbol, price, 24h change, volume, market cap in formatted columns
- **JSON** (`--format json`): Machine-readable with prices array and metadata
- **CSV** (`--output csv`): OHLCV historical data export to `${CLAUDE_SKILL_DIR}/data/`

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

## Error Handling

| Error | Cause | Solution |
|-------|-------|----------|
| `Unknown symbol: XYZ` | Invalid ticker | Check spelling, use `--list` to search |
| `Rate limit exceeded` | Too many API calls | Wait 60s, or add API key for higher limits |
| `Network error` | No internet | Check connection; cached data used automatically |
| `Cache stale` | Data older than TTL | Shown with warning, refreshes on next call |

The skill auto-manages rate limits: cache first, exponential backoff, yfinance fallback, stale cache as last resort.

## Examples

**Quick price check:**

```bash
python ${CLAUDE_SKILL_DIR}/scripts/price_tracker.py --symbol BTC
# Output: BTC (Bitcoin) $97,234.56 USD +2.34% (24h) | Vol: $28.5B | MCap: $1.92T
```

**Watchlist scan:**

```bash
python ${CLAUDE_SKILL_DIR}/scripts/price_tracker.py --watchlist top10
```

**Historical export:**

```bash
python ${CLAUDE_SKILL_DIR}/scripts/price_tracker.py --symbol ETH --period 90d --output csv
# Creates: ${CLAUDE_SKILL_DIR}/data/ETH_90d_[date].csv
```

## Resources

- `${CLAUDE_SKILL_DIR}/references/implementation.md` - Output formats, full config, integration guide, file map
- [CoinGecko API](https://www.coingecko.com/en/api) - Primary data source
- [yfinance](https://github.com/ranaroussi/yfinance) - Fallback for historical data