In my app, I have a function where I am reading data from a stored json file.

export async function readJson(filePath: string): Promise<Pokemon[]> {
  try {
    const segments = filePath.split("/");
    const fullPath = path.join(process.cwd(), "src", ...segments);
    const data = await fs.readFile(fullPath, "utf8");
    return JSON.parse(data);
  } catch (error) {
    console.error(error);
    return [];
  }
}

I call it like this

const pokedex = await readJson("/data/pokedex.json");

When I use this file in a server component, it works perfectly fine and displays the data I want. However when I try to do the same in a route handler, it works locally but not when deployed. I have a vercel cron job that is supposed to hit this endpoint on a schedule but I just get this error

[Error: ENOENT: no such file or directory, open '/var/task/src/data/pokedex.json'] {
  errno: -2,
  code: 'ENOENT',
  syscall: 'open',
  path: '/var/task/src/data/pokedex.json'
}

Are route handlers not supposed to be able to interact with the file system while deployed or am I doing this wrong? Should it be stored in a different folder? is the way I am referencing the path incorrect?