# Phase 1: Grundgerüst + Tippmechanik - Discussion Log (Assumptions Mode)

> **Audit trail only.** Do not use as input to planning, research, or execution agents.
> Decisions captured in CONTEXT.md — this log preserves the analysis.

**Date:** 2026-03-29
**Phase:** 01-Grundgerüst + Tippmechanik
**Mode:** assumptions
**Areas analyzed:** Screen Management Architecture, IndexedDB Schema, Typing Exercise Scope, Companion Placeholders, Level Progression, Adaptive Tempo

## Assumptions Presented

### Screen Management Architecture
| Assumption | Confidence | Evidence |
|------------|-----------|----------|
| All 5 screens as DOM containers, toggled via CSS classes with fade transitions | Likely | SPEC.md line 929: "5 Screens, nur einer sichtbar, Transitions mit CSS fade" |

### IndexedDB Schema
| Assumption | Confidence | Evidence |
|------------|-----------|----------|
| Create full schema with all 5 stores upfront, only implement read/write for progress + settings | Confident | FNDN-04 in REQUIREMENTS.md: "IndexedDB-Wrapper mit allen Stores" |

### Typing Exercise Scope
| Assumption | Confidence | Evidence |
|------------|-----------|----------|
| Only "Üben" phase implemented; "Entdecken" and "Wörter bauen" deferred to Phase 3 | Confident | TYPE-05, TYPE-06, TYPE-07 mapped to Phase 3 in REQUIREMENTS.md |

### Companion Placeholders
| Assumption | Confidence | Evidence |
|------------|-----------|----------|
| Emoji placeholders for companion selection, no companion during typing | Likely | SPEC.md line 930: "Platzhalter-Emojis"; ASST-03/04 mapped to Phase 2 |

## Corrections Made

No corrections — all assumptions confirmed.

## External Research Flagged

- Vite 6.x vanilla-ts template defaults and tsconfig
- Biome configuration for TypeScript strict + Vite
- IndexedDB wrapper approach: custom vs `idb` library