Tools

After code changes, has the agent check routes, errors and page behavior in the running Next.js app via /_next/mcp and agent-browser to confirm the change really works. Maintained by Next.js; needs Next.js 16.3+ (Turbopack) and agent-browser.

Drives a Next.js route to instant navigation under Cache Components: writes a failing @next/playwright instant() e2e test, pushes Suspense boundaries down to grow the static shell until it passes, and keeps the test as a regression guard. Requires Next.js 16.3+ with cacheComponents.

Official Next.js plugin shipped in the vercel/next.js repo: guides enabling and tuning Cache Components and Partial Prefetching, and verifies changes on a running dev server with the Next.js MCP and agent-browser.

GitHub's official spec-driven development toolkit: the specify CLI sets up spec, plan and task workflows for Copilot, Claude Code, Codex and other agents so the spec comes before the code, plus bug-fix and idea-evaluation flows. Needs Python 3.11+ and uv.

UI/UX design knowledge base plugin with searchable UI styles, color palettes, font pairings, charts and guidelines for 20+ tech stacks; generates complete design system recommendations by product type. Needs Python 3 installed locally.

UI design knowledge base skill: looks up UI styles, palettes, font pairings, charts and UX guidelines by product type and generates a full design system, covering 22 stacks including React, SwiftUI and Flutter. Needs Python 3 locally.

Local LLM inference engine in plain C/C++ with a command-line chat and an OpenAI-compatible HTTP server; pulls and runs GGUF models straight from Hugging Face. Supports Apple Silicon, CUDA, Vulkan and other hardware, plus low-bit quantization.

Migrates React projects and shadcn components from Radix UI to Base UI, one component at a time or the whole project on request. Prefers the shadcn CLI's base variants merged with user customizations, typechecks every step, and writes a per-component report in .migration/. From the shadcn/ui repo.

Official shadcn/ui skill: uses the shadcn CLI to read project config and component docs, then adds, searches, composes and fixes components following styling, form and accessibility rules. Can also start new projects from presets.

Official shadcn/ui CLI: initializes projects and adds component source to your codebase on demand, with switchable presets. Since v4 it offers --dry-run and --diff so agents can preview changes, and it comes with an agent skill.

MCP server built into the official shadcn CLI: lets agents browse and search components, blocks and templates in any configured registry, including private ones, and install them into your project in plain language. The project needs a components.json.

Minimal, extensible terminal AI agent that can write its own prompt templates, skills, extensions and themes. Offers print, JSON and RPC modes for scripting, plus a TypeScript SDK. Needs Node.js 22.19+.

Makes the agent answer in terse 'caveman' style to cut output tokens, compressing only prose while leaving code, commands and errors intact. Includes a local proxy that compresses logs, test output and other input. Works with Claude Code, Codex and 30+ other agents.

Multi-agent investment research framework where fundamental, sentiment, news and technical analysts, bull and bear researchers, a trader and risk managers debate a stock and produce a report and rating. Covers US, Hong Kong and A-shares. Needs Python and an LLM API key; not investment advice.

OpenAI's open-source general-purpose speech recognition model. The whisper command transcribes many languages, translates foreign speech into English and writes subtitle files. Needs FFmpeg; faster with a GPU.

JavaScript, TypeScript and WebAssembly runtime with built-in formatting, linting, testing and compilation. Scripts get no file, network or environment access unless granted with --allow-* flags, making agent-generated scripts safer to run.

Google's official open-source terminal agent using Gemini models with a 1M-token context. Built-in Google Search, file and shell tools, plus MCP support. Personal Google accounts get a free quota.

Engineering skill collection spanning define, plan, build, verify, review and ship, with /spec, /plan, /build, /test, /review and /ship commands, including TDD, code review and web performance audits. By Addy Osmani.

Addy Osmani's production-grade engineering skill pack covering spec, planning, implementation, testing, review and shipping, with commands like /spec, /plan, /build, /test, /review and /ship. Supports both Claude Code and Codex.

Reviews code changes before merge across five axes: correctness, readability, architecture, security and performance. Works on code and PRs from you, other agents or other people, judged by whether they improve overall code health. Part of Addy Osmani's agent-skills.

Open-source local design workbench and Claude Design alternative: builds web and mobile prototypes, slides, images and motion videos from a DESIGN.md system, exporting HTML, PDF, PPTX or MP4. MCP lets Claude Code and Codex use it. Needs the macOS or Windows app; Linux from source.

Helps agents build frontends that don't look templated: picks a design direction first, then tunes layout variance, motion intensity and information density. Also includes redesign audits, minimalist and brutalist styles, and design reference generation.

Microsoft's cross-browser end-to-end testing framework: one API drives Chromium, Firefox and WebKit, npx playwright test runs tests in parallel and isolation, with auto-waiting and trace replay for debugging failures.

All-in-one JavaScript and TypeScript toolchain: a single bun binary is a Node.js-compatible runtime, package manager, test runner and script runner, with noticeably faster installs and test runs.