To make your generator configurable, define an options type and pass it through the default function:

export type Options = {
  outfile: string;
  format?: "json" | "yaml";
  includeExamples?: boolean;
};

export default (options?: Options): GeneratorConstructor => {
  return {
    name: "MyGenerator",
    moduleImport: import.meta.filename,
    moduleConfig: options,
    factory: (...args) => factory(...args, options),
  };
};

Users configure your generator when adding it to their Vite config:

import myGenerator from "@my/generator";

export default {
  plugins: [
    devPlugin(apiurl, {
      generators: [
        myGenerator({
          outfile: "output.json",
          includeExamples: true,
        }),
      ],
    }),
  ],
}