[
  "`npm test` is failing. Find the cause, fix it, and confirm the whole suite passes.",
  "Usage records can now carry a `cache_write` token count. Make `costOf` bill it at the model's `cache_write` price, falling back to the input price when that is null, and add a test for both cases.",
  "Without editing any files: for a user who spends steadily all month, which allowance window in src/limits.mjs is usually the binding one, and is there anything wrong with how the windows are computed? Answer in under 150 words.",
  "Rename `costOf` to `requestCost` everywhere in src/ and test/, keep the behaviour identical, update the JSDoc, and run the tests."
]