---
kind: design
title: <specific non-UI contract or system design>
status: proposed
created_at: YYYY-MM-DD
updated_at: YYYY-MM-DD
related: []
tags: []
---

# <Specific non-UI contract or system design>

## 1. Issue and scope

<Specific issue or tasks this design addresses, observed impact, boundaries, and whether the solution is proposed or current. Link the owning records.>

## 2. Context and constraints

<Relevant current behavior, evidence for the issue, and constraints the solution must respect. Link to 03 for wider architecture.>

## 3. Solution

<Chosen approach and how it resolves the issue. Show ownership, boundaries, and flow; distinguish proposed behavior from implemented behavior.>

## 4. Contract and compatibility

<Observable inputs, outputs, defaults, errors, invariants, edge cases, and migration behavior needed to implement or use the solution. Omit inapplicable parts.>

## 5. Tradeoffs and open questions

<Why this solution was chosen, material costs or alternatives, and unresolved questions or follow-up. Link ADR decisions instead of restating them.>