MCP Crypto Wallet EVM

Instructions

Implementation Reference

• src/handlers/wallet.ts:294-315 (handler)

  The main handler function for 'wallet_call' that performs a static contract call using ethers.Wallet.call()

  export const callHandler = async (input: any): Promise<ToolResultSchema> => {
    try {
      if (!input.transaction) {
        return createErrorResponse("Transaction is required");
      }
  
      const wallet = await getWallet(input.wallet, input.password);
  
      if (!wallet.provider) {
        return createErrorResponse("Provider is required to call a contract, please set the provider URL");
      }
  
      const result = await wallet.call(input.transaction, input.blockTag);
  
      return createSuccessResponse(
      `Contract call executed successfully
        Result: ${result}
      `);
    } catch (error) {
      return createErrorResponse(`Failed to call contract: ${(error as Error).message}`);
    }
  };

• src/tools.ts:222-246 (schema)

  Input schema definition for the wallet_call tool, including parameters for wallet, transaction object, and blockTag

  {
    name: "wallet_call",
    description: "Call a contract method without sending a transaction",
    inputSchema: {
      type: "object",
      properties: {
        wallet: { type: "string", description: "The wallet (private key, mnemonic, or JSON). If not provided, uses PRIVATE_KEY environment variable if set." },
        transaction: { 
          type: "object", 
          description: "The transaction to call",
          properties: {
            to: { type: "string" },
            from: { type: "string" },
            data: { type: "string" },
            value: { type: "string" },
            gasLimit: { type: "string" },
            gasPrice: { type: "string" }
          },
          required: ["to"]
        },
        blockTag: { type: "string", description: "Optional block tag (latest, pending, etc.)" }
      },
      required: ["transaction"]
    }
  },

• src/tools.ts:556-608 (registration)

  The handlers dictionary where 'wallet_call' is registered to map to the callHandler function

  export const handlers: HandlerDictionary = {
    // Provider Methods
    "wallet_provider_set": setProviderHandler,
    // Wallet Creation and Management
    "wallet_create_random": createWalletHandler,
    "wallet_from_private_key": fromPrivateKeyHandler,
    "wallet_from_mnemonic": fromMnemonicHandler,
    "wallet_from_encrypted_json": fromEncryptedJsonHandler,
    "wallet_encrypt": encryptWalletHandler,
  
    // Wallet Properties
    "wallet_get_address": getAddressHandler,
    "wallet_get_public_key": getPublicKeyHandler,
    "wallet_get_private_key": getPrivateKeyHandler,
  
    // Blockchain Methods
    "wallet_get_balance": getBalanceHandler,
    "wallet_get_chain_id": getChainIdHandler,
    "wallet_get_gas_price": getGasPriceHandler,
    "wallet_get_transaction_count": getTransactionCountHandler,
    "wallet_call": callHandler,
  
    // Transaction Methods
    "wallet_send_transaction": sendTransactionHandler,
    "wallet_sign_transaction": signTransactionHandler,
    "wallet_populate_transaction": populateTransactionHandler,
  
    // Signing Methods
    "wallet_sign_message": signMessageHandler,
    "wallet_sign_typed_data": signTypedDataHandler,
    "wallet_verify_message": verifyMessageHandler,
    "wallet_verify_typed_data": verifyTypedDataHandler,
  
    // Provider Methods
    "provider_get_block": getBlockHandler,
    "provider_get_transaction": getTransactionHandler,
    "provider_get_transaction_receipt": getTransactionReceiptHandler,
    "provider_get_code": getCodeHandler,
    "provider_get_storage_at": getStorageAtHandler,
    "provider_estimate_gas": estimateGasHandler,
    "provider_get_logs": getLogsHandler,
    "provider_get_ens_resolver": getEnsResolverHandler,
    "provider_lookup_address": lookupAddressHandler,
    "provider_resolve_name": resolveNameHandler,
  
    // Network Methods
    "network_get_network": getNetworkHandler,
    "network_get_block_number": getBlockNumberHandler,
    "network_get_fee_data": getFeeDataHandler,
  
    // Mnemonic Methods
    "wallet_create_mnemonic_phrase": createMnemonicPhraseHandler
  };