ADR 0150: Inline SVG empty-home agent mark

• Status: Superseded by ADR 0152
• Date: 2026-09-04
• Deciders: PI-Desktop core
• Related: D291, E2E-046, E2E-099, US-UI-17

Context

The empty-home hero used a raster sprite atlas with randomized pose groups, discrete frame changes, and a hover shortcut that accelerated playback. The result was visually loud in the central conversation area and added asset, timer, and reduced-motion state to a decorative mark.

Decision

Replace the sprite with a 100px inline SVG agent mark. A thin orbit and signal point rotate slowly around a compact core; the core breathes gently and the eyes blink occasionally. The animation is deterministic, pointer hover does not change its cadence, and prefers-reduced-motion: reduce freezes the mark. The SVG remains decorative with aria-hidden="true" and preserves the existing 100px layout slot.

Consequences

• Empty-home branding is quieter and remains readable across light and dark themes through semantic color tokens.
• The component has no raster atlas, random selection, timers, or hover state.
• CSS owns the motion and can disable it without changing the rendered SVG.
• The old sprite asset can remain available for historical source context but is no longer part of the renderer path.

Alternatives rejected

• Keep the existing atlas and tune pause durations: this would retain the visually noisy pixel-art treatment and interaction-specific timer state.
• Generate another raster mascot: this would add asset maintenance while preserving the same theme and reduced-motion limitations.