Para Wallet MCP Server

Instructions

Implementation Reference

• src/tools/sign-raw.ts:24-53 (handler)

  The handler function for the 'sign_raw' tool, which processes arguments, validates input format, and calls the API.

  export async function handler(client: ParaClient, args: Record<string, unknown>) {
    const walletId = args.walletId as string;
    const data = args.data as string;
  
    if (!data.startsWith('0x') || !/^0x[0-9a-fA-F]+$/.test(data)) {
      return {
        content: [
          {
            type: 'text' as const,
            text: 'Error: data must be a 0x-prefixed hex string (e.g. "0x48656c6c6f"). To sign a UTF-8 string, first convert it to hex.',
          },
        ],
        isError: true,
      };
    }
  
    const result = await client.requestWithRetry<SignRawResponse>(
      `/v1/wallets/${walletId}/sign-raw`,
      { method: 'POST', body: { data } },
    );
  
    return {
      content: [
        {
          type: 'text' as const,
          text: JSON.stringify(result, null, 2),
        },
      ],
    };
  }

• src/tools/sign-raw.ts:4-22 (schema)

  The MCP definition object for 'sign_raw', including its name, description, and input schema.

  export const definition = {
    name: 'sign_raw',
    description:
      'Sign arbitrary data with a wallet via MPC. The data must be a 0x-prefixed hex string. The wallet must be in "ready" status. Returns the signature.',
    inputSchema: {
      type: 'object' as const,
      properties: {
        walletId: {
          type: 'string',
          description: 'The wallet ID to sign with',
        },
        data: {
          type: 'string',
          description: 'Data to sign as a 0x-prefixed hex string (e.g. "0x48656c6c6f")',
        },
      },
      required: ['walletId', 'data'],
    },
  };

• src/types.ts:52-60 (schema)

  Zod schema definitions for 'sign_raw' request and response types.

  export const SignRawRequestSchema = z.object({
    data: z.string().regex(/^0x[0-9a-fA-F]+$/, 'data must be a 0x-prefixed hex string'),
  });
  export type SignRawRequest = z.infer<typeof SignRawRequestSchema>;
  
  export const SignRawResponseSchema = z.object({
    signature: z.string(),
  });
  export type SignRawResponse = z.infer<typeof SignRawResponseSchema>;

• src/index.ts:30-30 (registration)

  The registration of the 'sign_raw' tool into the main tool list array.

  const tools = [createWallet, getWallet, signRaw, listWallets, waitForWallet];