# Home screen background photographs

`/home` returns an unrestricted array of scheduled background photographs. It commonly contains four or five weeks, but may contain any number. The API does not reject gaps, overlaps, out-of-order items or multiple simultaneously active photographs. Those concerns belong to future administrative tooling and deterministic app display policy.

Each entry has a stable ID, one HTTPS image URL, optional `caption`, optional `photographer` and optional `source`, and required inclusive `startsAt` / exclusive `endsAt` timestamps. Credit names and captions support Unicode. Only one image resolution is provided in this version.

## Schedule convention

Operationally, photos are normally scheduled Monday at 00:00 on a **fixed EST UTC−05:00 clock**, including during daylight saving time. This is Monday 05:00 UTC, which appears as 01:00 in Toronto during daylight saving time. Each usual period is seven days. The API represents the configured timestamps and does **not** enforce this convention.

## App display and caching

Download current images first and future images opportunistically. Switch based on cached timestamps without requiring a network call. If multiple photos are valid, the client should apply a deterministic tie-breaker (suggested: latest `startsAt`, then lexical ID). If no photo is valid, fall back to the most recently cached photo **only if its usage rights permit**; otherwise use the bundled fallback. The API currently has no separate rights-expiry field, so any licensing constraints must be addressed before shipping content that cannot be reused after its schedule.

If the image bytes at a URL change, issue a new photo ID (or later add a revision field) to invalidate cached image bytes. A photograph can be rescheduled without changing its identity. The API does not perform image processing or manage uploads in this phase.