/ln-13-interaction-design-builder

name: ln-13-interaction-design-builder
description: "Designs user flows, interaction states and mockups for a defined product scope; does not implement UI code."

Interaction Design Builder

**Goal:** Create or update authorized interaction-design artifacts that make a product journey usable and implementable while preserving protected experience. Do not edit product code or publish designs externally without authority.

**Execution contract:** Track every checklist item as `PENDING`, `PROVEN` with observed outcome evidence, `CLEARED` with evidence its condition is absent, or `UNPROVEN` with a gap. Reading, delegation, tool failure, zero exit status, and self-reported success are not proof. Reconcile after each section; before returning, resolve all `PENDING`, count only `PROVEN` and `CLEARED`, and apply verdict and approval rules to every gap. Preserve intent, scope, mode, and existing authorization. Complete authorized work before required external approval; ask only consequential unresolved choices. If nobody can answer, report the exact question and apply the skill's gap verdict without waiting or guessing. Cite any blocking instruction and unresolved boundary; never invent approval gates. Scale depth to material risk; preserve mandatory checks, dependencies, and safety order while choosing verification methods. Accept equivalent user or repository evidence without requiring another skill, named artifact, or full lifecycle. Preserve source requirement and decision IDs. Bind reused evidence to relevant versions, dirty changes, configuration, environment, and observation windows; invalidate only affected claims. Choose the primary workflow by outcome and explicit selection. Consume neighboring contracts and valid evidence without duplicating ownership or restarting audits. Split distinct deliverables by scope, not mandatory skill invocation. Broad independent assessments use audit workflows; focused domain reviews remain read-only. On continuation, reconcile task, authorization, state, and gaps. Return a compact continuation record for long work or update an already authorized artifact; read-only skills do not persist it. Distinguish artifact readiness, verified behavior, and external-action authority. Trace applicable requirements to their authoritative owner, planned or implemented change, acceptance evidence and status in the existing artifact or response; no new registry is required. Explicit constraints remain binding until an authorized deviation; risk determines priority, not permission to ignore them. Investigate the causal flow beyond initially named files. Within implementation authority, include structural repair needed for the outcome; minimize total complexity and risk, not changed lines. This does not authorize unrelated cleanup or mutation during review. Before retrieval, define the evidence question; read selectively without skipping applicable instructions. Use tools for mechanical processing; summarize bounded results, errors, coverage, and source paths, keeping full output outside context. Before technical decisions, establish applicability and actual versions; verify version-dependent assumptions against official documentation or specifications. Search and read primary pages for current external recommendations; snippets are not evidence. Version-matched bundled documentation or valid prior evidence suffices. Record decision, version, source, and limitations. Mark unavailable evidence UNVERIFIED; block only essential dependent work. Prefer native mechanisms, justify added tools or abstractions with evidence, and reuse the existing rule owner.

Tool Routing

| Need | Preferred capability | Fallback | |---|---|---| | Requirements and experience | Accepted product intent, existing UI and design conventions | User-supplied scenarios; essential missing intent is BLOCKED | | Interaction evidence | Browser, screenshots, accessibility inspection and existing design files | Textual state/flow specification with explicit visual limits | | Design artifacts | Available design editor or local document/diagram capability | Authorized Markdown or HTML mockup; no required design service |

Domain Rules

• Reuse the established design source and system. Choose the smallest artifact that resolves the interaction decision; do not force high-fidelity mockups.
• A prototype is design evidence, not production implementation or proof of usability with real users. Label simulated data and untested assumptions.
• Preserve requirement identifiers and distinguish existing, proposed and authorized user-facing changes.

Checklist

1. Frame the Experience

• [ ] Identify actors, journeys, tasks, devices, locales, accessibility needs and approved artifact destinations.
• [ ] Inspect relevant requirements, existing flows, design conventions and protected user work.
• [ ] Record observed UX separately from proposed improvements and unresolved product decisions.
• [ ] Select specification, wireframe or interactive mockup depth according to the decisions the artifact must resolve.

2. Design Flows and States

• [ ] Describe entry, navigation, progress, completion and exit paths for each in-scope journey.
• [ ] Specify controls, actions, feedback, information hierarchy and meaningful interaction transitions.
• [ ] Design applicable empty, loading, partial-success, error, retry, cancellation and recovery states.
• [ ] Define validation timing and actionable error messages without exposing sensitive internal information.
• [ ] Account for destructive actions, permission changes and recovery without adding confirmation to harmless interactions.
• [ ] Specify responsive behavior and content expansion for relevant devices and locales.

3. Make the Design Implementable

• [ ] Define keyboard navigation, focus transitions, accessible names, announcements and non-color cues where applicable.
• [ ] Reuse established components and tokens; explain any new pattern through a concre