# Task Breakdown: 001-weather-cli

## 1. Setup [P1]
- [ ] Task Setup: `uv init weather-cli && cd weather-cli && uv add httpx click pytest ruff mypy`
- [ ] CI: Initialize git repo and commit setup.

## 2. API Key Management [US2] [P1]
- [ ] Key verification logic: Throw exception if `WEATHER_API_KEY` is missing from environment.

## 3. Data Entities [US1] [P1] [TDD]
- [ ] Write `CityWeather` dataclass with `temp` and `condition`.
- [ ] Write tests for entity validation.

## 4. Weather Logic [US1] [US3] [P1] [TDD]
- [ ] Implement `WeatherService` using `httpx` to call OpenWeather API.
- [ ] Support units (metric/imperial).
- [ ] Handle 404/City not found and API errors.
- [ ] Write mocked API tests for service with unit coverage.

## 5. CLI Interface [US1] [US3] [P2]
- [ ] Implement command line interface using `click`.
- [ ] Integrate service and entities.

## 6. Final Polish [P1]
- [ ] Verify against `quickstart.md` scenarios.
- [ ] Run full test suite with `pytest`.
- [ ] Format with `ruff`.
- [ ] Final commit.