crypto-pegmon-mcp

Instructions

Fetch the current price of a USD-pegged stablecoin in USD and calculate peg deviation.

Args:
    coin (str): The symbol of the stablecoin (e.g., 'usdt', 'usdc', 'dai').

Returns:
    str: A string with the current price and peg deviation in Markdown format.

Implementation Reference

• main.py:107-127 (handler)

  The handler function for the 'get_current_price' tool. It takes a stablecoin symbol, fetches its current USD price via CoinGecko API, computes the peg deviation from $1, and returns a formatted Markdown string with the price and deviation.

  def get_current_price(coin: str) -> str:
      """
      Fetch the current price of a USD-pegged stablecoin in USD and calculate peg deviation.
  
      Args:
          coin (str): The symbol of the stablecoin (e.g., 'usdt', 'usdc', 'dai').
  
      Returns:
          str: A string with the current price and peg deviation in Markdown format.
      """
      if coin.lower() not in STABLECOINS:
          return f"Error: Unsupported stablecoin. Choose from {list(STABLECOINS.keys())}"
      
      coin_id = STABLECOINS[coin.lower()]["id"]
      try:
          data = cg.get_price(ids=coin_id, vs_currencies="usd")
          price = data[coin_id]["usd"]
          deviation = (price - 1.0) * 100  # Calculate deviation as percentage
          return f"**{coin.upper()} Current Price**: ${price:.4f}, Peg Deviation: {deviation:.2f}%"
      except Exception as e:
          return f"Error fetching price for {coin}: {str(e)}"

• main.py:106-106 (registration)

  The @mcp.tool() decorator registers the get_current_price function as an MCP tool. The tool name is the function name 'get_current_price'.

  @mcp.tool()

• main.py:108-116 (schema)

  Docstring defining the input schema (coin: str parameter) and output format for the tool.

  """
  Fetch the current price of a USD-pegged stablecoin in USD and calculate peg deviation.
  
  Args:
      coin (str): The symbol of the stablecoin (e.g., 'usdt', 'usdc', 'dai').
  
  Returns:
      str: A string with the current price and peg deviation in Markdown format.
  """

• main.py:15-83 (helper)

  Global STABLECOINS dictionary providing CoinGecko IDs for supported stablecoins, used by get_current_price to validate input and fetch data.

  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."
      }