MCP Ethers Wallet

Implementation Reference

• src/tools/core.ts:189-214 (handler)

  The core handler logic for the 'loadWallet' tool. Creates an ethers.js Wallet instance from the provided private key, optionally persists it to process.env.WALLET_PRIVATE_KEY and configures it as the signer on the shared ethersService instance, then returns a success response with the wallet address.

      async ({ privateKey, saveToEnv = true }) => {
        try {
          const wallet = new ethers.Wallet(privateKey);
          
          if (saveToEnv) {
            process.env.WALLET_PRIVATE_KEY = privateKey;
            
            // Update the ethersService with the new wallet
            const signer = new ethers.Wallet(privateKey, ethersService.provider);
            ethersService.setSigner(signer);
          }
          
          return {
            content: [{ 
              type: "text", 
              text: `
  Wallet loaded successfully:
  Address: ${wallet.address}
  ${saveToEnv ? "Private key has been saved to environment variables for this session." : ""}
  `
            }]
          };
        } catch (error) {
          return createErrorResponse(error, 'loading wallet');
        }
      }

• src/tools/core.ts:181-188 (schema)

  Zod input schema validation for the 'loadWallet' tool parameters: requires a privateKey string and optional saveToEnv boolean (defaults to true).

  {
    privateKey: z.string().describe(
      "The private key of the wallet to load. Should start with '0x'."
    ),
    saveToEnv: z.boolean().optional().describe(
      "Optional. If true, the private key will be saved to the server's environment variables for this session. Default is true."
    )
  },

• src/tools/core.ts:179-215 (registration)

  Registration of the 'loadWallet' MCP tool on the server using server.tool(), including inline schema and handler implementation within the registerCoreTools function.

    server.tool(
      "loadWallet",
      {
        privateKey: z.string().describe(
          "The private key of the wallet to load. Should start with '0x'."
        ),
        saveToEnv: z.boolean().optional().describe(
          "Optional. If true, the private key will be saved to the server's environment variables for this session. Default is true."
        )
      },
      async ({ privateKey, saveToEnv = true }) => {
        try {
          const wallet = new ethers.Wallet(privateKey);
          
          if (saveToEnv) {
            process.env.WALLET_PRIVATE_KEY = privateKey;
            
            // Update the ethersService with the new wallet
            const signer = new ethers.Wallet(privateKey, ethersService.provider);
            ethersService.setSigner(signer);
          }
          
          return {
            content: [{ 
              type: "text", 
              text: `
  Wallet loaded successfully:
  Address: ${wallet.address}
  ${saveToEnv ? "Private key has been saved to environment variables for this session." : ""}
  `
            }]
          };
        } catch (error) {
          return createErrorResponse(error, 'loading wallet');
        }
      }
    );