ADR-004: Single-scenario MVP

Status: Accepted Source: prd.md §19

Context

The research PDF lists 4 demo scenarios; the mockup shows 5 issue types. A 2-day hackathon cannot deliver four distinct end-to-end flows with credibility — the product risk is shipping shallow versions of all four rather than one convincing one.

Decision

The MVP implements scenario 1 (screen damage → repair) only. Scenario 2 (inventory deflection) is P1 stretch. Scenarios 3 and 4 are out of scope.

Consequences

• The demo arc stays tight: one journey, told well. The pitch closing (prd.md §20) translates the same architecture to fraud, inventory, and retention to make the scale story explicit.
• Adding a new scenario is "+1 event source +1 action handler +1 dashboard tab" — captured in prd.md §20 "Pattern Reusability". The architectural cost is bounded.
• Reviewers may ask "why isn't fraud also live?" — answered by "this is the slice that proves the pattern; the others are mechanical".

Cross-references

• prd.md §20 — the pattern-reusability pitch the single-scenario decision enables.