harness-kit

Visual + UX design defaults for new UIs. Material Design 3, dark/light theme, modern type, Behance-grade polish, i18n (en, pt-BR, es), context-aware favicon. No emojis and no em-dashes; use MD3/modern icons instead. Apply when building something new. Project conventions in .claude/conventions/web.md override these defaults.

Re-install / upgrade harness-kit in the current project to the version bundled in the installed plugin. Run after /plugin update harness-kit fetches a newer plugin version.

Generate a Product Requirements Prompt for engineering handoff. Needs an approved PRD. Sensors, link validation, and eval gates.

Install the harness-kit pipeline into the current project. Copies agents, slash commands, skills, hooks, and the status bar into the project's .claude/, plus AGENTS.md and CLAUDE.md at the repo root. Run after adding the harness-kit plugin from the marketplace.

Design any system from scratch into a rigorous System Design Doc. Generic fallback when no topic-specific playbook fits. Sensors and evals gate.

Design a distributed rate limiter at scale, policy model, enforcement layers (edge/gateway/service), algorithms (token bucket, sliding window), hot keys, fail-open vs fail-closed, multi-region, shadow mode. Topic playbook from the System Design series EP (Rate Limit

Adversarial design review of a System Design Doc. Interrogates the staff questions, finds the cost-explosion and failure risks, returns a verdict. Sensors and evals gate.

Design a web-scale search engine (crawler, processing, indexing, query serving). Topic playbook from the System Design series EP24. Use when the system is a search engine, web crawler, or large-scale retrieval system. Sensors and evals gate.

Design a URL shortener at scale (TinyURL / bit.ly style): short-code generation, redirect path, cache, partitioning, analytics, abuse. Topic playbook from the System Design series EP22. Use when the system is a link shortener, redirect service, or any read-heavy key-to-value lookup at scale. Sensors and evals gate.

Backend engineering conventions for team. Java/Kotlin servers. Project conventions in .claude/conventions/backend.md override these defaults.

DevOps engineering conventions for team. CI/CD, infra-as-code, observability. Project conventions in .claude/conventions/devops.md override these defaults.

Mobile engineering conventions for team. iOS and Android. Project conventions in .claude/conventions/mobile.md override these defaults.

Web frontend engineering conventions for team. Vue.js stack. Project conventions in .claude/conventions/web.md override these defaults.

Generate a Product Requirements Document for an team squad. Business-facing artifact. Sensors and evals gate.