Mailchimp MCP Server

Instructions

Implementation Reference

• src/tools/index.ts:907-924 (handler)

  The handler logic for the 'list_folders' tool within the handleToolCall switch statement. It calls the MailchimpService.listFolders() method, maps the results to include only id, name, and count, and returns the data as a formatted JSON text response.

  case "list_folders":
    const folders = await service.listFolders();
    return {
      content: [
        {
          type: "text",
          text: JSON.stringify(
            folders.folders.map((f) => ({
              id: f.id,
              name: f.name,
              count: f.count,
            })),
            null,
            2
          ),
        },
      ],
    };

• src/tools/index.ts:322-330 (registration)

  The tool registration object defining the 'list_folders' tool, including its name, description, and input schema (which requires no parameters). This array is used by getToolDefinitions to expose the tool via MCP.

  {
    name: "list_folders",
    description: "List all campaign folders",
    inputSchema: {
      type: "object",
      properties: {},
      required: [],
    },
  },

• src/types/index.ts:691-702 (schema)

  TypeScript interface defining the structure of a Mailchimp folder object, used in the return type of listFolders() and mapped in the handler.

  export interface MailchimpFolder {
    id: string;
    name: string;
    count: number;
    _links?: Array<{
      rel: string;
      href: string;
      method: string;
      targetSchema?: string;
      schema?: string;
    }>;
  }

• src/services/mailchimp.ts:261-262 (helper)

  Helper method in MailchimpService that performs the actual API call to fetch campaign folders using makePaginatedRequest, invoked by the tool handler.

  async listFolders(): Promise<{ folders: MailchimpFolder[] }> {
    return await this.makePaginatedRequest("/campaign-folders", "name", "ASC");