get_historical_data
Fetch historical price data for USD-pegged stablecoins, displaying date, price, and deviation in a Markdown table. Specify the stablecoin symbol and optional days for analysis.
Instructions
Fetch historical price data for a USD-pegged stablecoin and return as a Markdown table.
Args:
coin (str): The symbol of the stablecoin (e.g., 'usdt', 'usdc', 'dai').
days (int, optional): Number of days for historical data. Defaults to 7.
Returns:
str: A Markdown table with date, price, and deviation.Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| coin | Yes | ||
| days | No |
Implementation Reference
- main.py:130-160 (handler)The handler function for the 'get_historical_data' tool. It fetches historical price data from CoinGecko API, computes deviations from $1 peg, and returns a Markdown table. Registered via @mcp.tool() decorator.
@mcp.tool() def get_historical_data(coin: str, days: int = 7) -> str: """ Fetch historical price data for a USD-pegged stablecoin and return as a Markdown table. Args: coin (str): The symbol of the stablecoin (e.g., 'usdt', 'usdc', 'dai'). days (int, optional): Number of days for historical data. Defaults to 7. Returns: str: A Markdown table with date, price, and deviation. """ if coin.lower() not in STABLECOINS: return f"Error: Unsupported stablecoin. Choose from {list(STABLECOINS.keys())}" coin_id = STABLECOINS[coin.lower()]["id"] try: # Fetch historical data for the specified number of days data = cg.get_coin_market_chart_by_id(id=coin_id, vs_currency="usd", days=days) prices = [(datetime.fromtimestamp(item[0]/1000).strftime("%Y-%m-%d"), item[1]) for item in data["prices"]] # Create DataFrame for prices and deviations df = pd.DataFrame(prices, columns=["Date", "Price"]) df["Deviation (%)"] = (df["Price"] - 1.0) * 100 # Convert to Markdown table markdown_table = df.to_markdown(index=False, floatfmt=".4f") return f"**{coin.upper()} Historical Data (Last {days} Days)**:\n\n{markdown_table}" except Exception as e: return f"Error fetching historical data for {coin}: {str(e)}" - main.py:15-84 (helper)Global dictionary mapping stablecoin symbols to their CoinGecko IDs and descriptions. Used by get_historical_data for validation and ID lookup.
STABLECOINS = { "usdt": { "id": "tether", "description": "Tether's USD-pegged stablecoin, centrally issued." }, "usdc": { "id": "usd-coin", "description": "Circle's USD-backed stablecoin, widely used in DeFi." }, "dai": { "id": "dai", "description": "Decentralized stablecoin by MakerDAO, collateralized by crypto." }, "busd": { "id": "binance-usd", "description": "Binance's USD-pegged stablecoin, centrally managed." }, "tusd": { "id": "true-usd", "description": "TrueUSD, a USD-backed stablecoin by TrustToken." }, "frax": { "id": "frax", "description": "Fractional-algorithmic USD stablecoin by Frax Finance." }, "usdd": { "id": "usdd", "description": "TRON's USD-pegged stablecoin, centrally issued." }, "usds": { "id": "usds", "description": "USD-pegged stablecoin, focused on stability." }, "susds": { "id": "susds", "description": "Staked USDS, yield-bearing stablecoin." }, "eusde": { "id": "ethena-staked-usde", "description": "Ethena's staked USD stablecoin, yield-bearing." }, "usdy": { "id": "ondo-us-dollar-yield", "description": "Ondo's USD yield stablecoin, designed for returns." }, "pyusd": { "id": "paypal-usd", "description": "PayPal's USD-pegged stablecoin for payments." }, "gusd": { "id": "gemini-dollar", "description": "Gemini Dollar, USD-backed by Gemini Trust." }, "usdp": { "id": "paxos-standard", "description": "Paxos Standard, a regulated USD stablecoin." }, "aave-usdc": { "id": "aave-usdc", "description": "Aave's USD-pegged stablecoin for lending." }, "curve-usd": { "id": "curve-usd", "description": "Curve Finance's USD stablecoin for DeFi pools." }, "mim": { "id": "magic-internet-money", "description": "Magic Internet Money, a decentralized USD stablecoin." } }