LunchMoney MCP Server

Instructions

Implementation Reference

• src/tools/crypto.ts:11-42 (handler)

  The handler function that fetches the user's cryptocurrency assets from the LunchMoney API endpoint `/crypto`, handles errors, and returns the assets as a JSON string in the MCP response format.

  async () => {
      const { baseUrl, lunchmoneyApiToken } = getConfig();
      
      const response = await fetch(`${baseUrl}/crypto`, {
          headers: {
              Authorization: `Bearer ${lunchmoneyApiToken}`,
          },
      });
  
      if (!response.ok) {
          return {
              content: [
                  {
                      type: "text",
                      text: `Failed to get crypto assets: ${response.statusText}`,
                  },
              ],
          };
      }
  
      const data = await response.json();
      const cryptoAssets: Crypto[] = data.crypto;
      
      return {
          content: [
              {
                  type: "text",
                  text: JSON.stringify(cryptoAssets),
              },
          ],
      };
  }

• src/tools/crypto.ts:8-43 (registration)

  Registers the 'get_all_crypto' tool on the MCP server with its description, empty input schema, and inline handler function.

      "get_all_crypto",
      "Get a list of all cryptocurrency assets associated with the user",
      {},
      async () => {
          const { baseUrl, lunchmoneyApiToken } = getConfig();
          
          const response = await fetch(`${baseUrl}/crypto`, {
              headers: {
                  Authorization: `Bearer ${lunchmoneyApiToken}`,
              },
          });
  
          if (!response.ok) {
              return {
                  content: [
                      {
                          type: "text",
                          text: `Failed to get crypto assets: ${response.statusText}`,
                      },
                  ],
              };
          }
  
          const data = await response.json();
          const cryptoAssets: Crypto[] = data.crypto;
          
          return {
              content: [
                  {
                      type: "text",
                      text: JSON.stringify(cryptoAssets),
                  },
              ],
          };
      }
  );

• src/index.ts:31-31 (registration)

  Invokes the registration of crypto tools, including 'get_all_crypto', on the main MCP server instance.

  registerCryptoTools(server);

• src/tools/crypto.ts:6-100 (helper)

  Helper function that registers both crypto-related tools on the MCP server.

  export function registerCryptoTools(server: McpServer) {
      server.tool(
          "get_all_crypto",
          "Get a list of all cryptocurrency assets associated with the user",
          {},
          async () => {
              const { baseUrl, lunchmoneyApiToken } = getConfig();
              
              const response = await fetch(`${baseUrl}/crypto`, {
                  headers: {
                      Authorization: `Bearer ${lunchmoneyApiToken}`,
                  },
              });
  
              if (!response.ok) {
                  return {
                      content: [
                          {
                              type: "text",
                              text: `Failed to get crypto assets: ${response.statusText}`,
                          },
                      ],
                  };
              }
  
              const data = await response.json();
              const cryptoAssets: Crypto[] = data.crypto;
              
              return {
                  content: [
                      {
                          type: "text",
                          text: JSON.stringify(cryptoAssets),
                      },
                  ],
              };
          }
      );
  
      server.tool(
          "update_manual_crypto",
          "Update a manually-managed cryptocurrency asset balance",
          {
              input: z.object({
                  crypto_id: z
                      .number()
                      .describe("ID of the crypto asset to update"),
                  balance: z
                      .number()
                      .optional()
                      .describe("Updated balance of the crypto asset"),
              }),
          },
          async ({ input }) => {
              const { baseUrl, lunchmoneyApiToken } = getConfig();
              
              const body: any = {};
              
              if (input.balance !== undefined) {
                  body.balance = input.balance.toString();
              }
              
              const response = await fetch(`${baseUrl}/crypto/manual/${input.crypto_id}`, {
                  method: "PUT",
                  headers: {
                      Authorization: `Bearer ${lunchmoneyApiToken}`,
                      "Content-Type": "application/json",
                  },
                  body: JSON.stringify(body),
              });
  
              if (!response.ok) {
                  return {
                      content: [
                          {
                              type: "text",
                              text: `Failed to update crypto asset: ${response.statusText}`,
                          },
                      ],
                  };
              }
  
              const result = await response.json();
              
              return {
                  content: [
                      {
                          type: "text",
                          text: JSON.stringify(result),
                      },
                  ],
              };
          }
      );
  }