Discogs MCP Server

Instructions

Implementation Reference

• src/tools/userLists.ts:31-45 (handler)

  The MCP tool handler for 'get_list', including name, description, parameters schema, and execute function that instantiates ListService and calls getList on the provided args.

  export const getListTool: Tool<FastMCPSessionAuth, typeof ListIdParamSchema> = {
    name: 'get_list',
    description: `Get a list by ID`,
    parameters: ListIdParamSchema,
    execute: async (args) => {
      try {
        const listService = new ListService();
        const list = await listService.getList(args);
  
        return JSON.stringify(list);
      } catch (error) {
        throw formatDiscogsError(error);
      }
    },
  };

• src/types/list.ts:51-53 (schema)

  Zod input schema for the get_list tool parameters, requiring a numeric list_id.

  export const ListIdParamSchema = z.object({
    list_id: z.number(),
  });

• src/tools/userLists.ts:47-50 (registration)

  Registration of the get_list tool (and get_user_lists) on the FastMCP server instance.

  export function registerUserListsTools(server: FastMCP): void {
    server.addTool(getUserListsTool);
    server.addTool(getListTool);
  }

• src/services/list.ts:22-38 (helper)

  Core helper function in ListService that performs the Discogs API request to fetch the list by ID and validates the response with ListSchema.

  async getList({ list_id }: ListIdParam): Promise<List> {
    try {
      const response = await this.request<List>(`/${list_id}`);
  
      // Validate the response using Zod schema
      const validatedResponse = ListSchema.parse(response);
      return validatedResponse;
    } catch (error) {
      // If it's already a Discogs error, just rethrow it
      if (isDiscogsError(error)) {
        throw error;
      }
  
      // For validation errors or other unexpected errors, wrap them
      throw new Error(`Failed to get list: ${String(error)}`);
    }
  }