astro-website/openspec/changes/archive/2026-02-11-remember-theme/specs/interaction-tracking-taxonomy/spec.md

ADDED Requirements

Requirement: Theme switch event taxonomy

The tracking taxonomy MUST define an event for theme switching.

The event name MUST be theme_switch.

The theme_switch event MUST include, at minimum:

• target_id
• placement
• theme

The event SHOULD include prev_theme when available.

The taxonomy MUST define the target_id namespace for theme switching as:

• theme.switch.<theme>

The taxonomy MUST define the placement value for the theme switcher notch as:

• theme_notch

Scenario: Theme switch target_id is deterministic

• WHEN a user selects light theme using the theme notch
• THEN the event is emitted with target_id=theme.switch.light and placement=theme_notch