Tools

Controls your local Chrome over CDP to navigate, click, type, take screenshots and scrape data, reusing logged-in sessions. Official browser-use skill; install the browser-use CLI with uv first.

Flags and rewrites AI-sounding text using 25 patterns drawn from Wikipedia's 'Signs of AI writing', keeping the meaning without inventing facts. Give it a writing sample to match your own voice.

166 research skills maintained by K-Dense (formerly Claude Scientific Skills), spanning bioinformatics, cheminformatics, clinical research, materials and physics, including unified access to 78 public databases such as PubChem and UniProt. Works with Claude Code, Codex and Cursor.

Skills from security firm Trail of Bits: 40+ plugins for code auditing, CodeQL and Semgrep static analysis, differential review, smart-contract and cryptography audits, fuzzing and more. Also installable as a Claude Code or Codex plugin marketplace.

Forces red-green-refactor: write a test and watch it fail, then write the minimum code to pass. Any code written without a verified failing test gets deleted and redone. From the Superpowers workflow.

A disciplined process for hard bugs and performance regressions: build a reliable reproduction loop, reproduce and minimize, form hypotheses, instrument to verify, then fix and add a regression test, redacting secrets in output. By Matt Pocock.

Develops a design philosophy first, then draws posters, illustrations and other static visuals in code, exporting PNG or PDF. Emphasizes original work rather than copying existing artists. Official Anthropic skill.

Makes GIFs that follow Slack's recommended size, frame rate, color and length for emoji (128x128) and message GIFs (480x480), with animation tips and tools to assemble and validate them. Built on Python and Pillow. Official Anthropic skill.

Drives local web apps with Python Playwright scripts to verify features, debug the UI, take screenshots and read browser logs. Includes helper scripts to start and stop dev servers. Official Anthropic skill.

Creates, edits and analyzes Excel spreadsheets: formulas, formatting, charts and data cleaning, plus conversion between CSV, TSV and other tabular formats. The official Anthropic skill behind Claude's document features; source-available, not open source.

Skill pack from YC president Garry Tan: slash commands such as /office-hours, /plan-ceo-review, /review, /qa and /ship play CEO, engineering manager, designer, QA and release engineer. Needs Git and Bun; clone the repo and run ./setup as the README describes.

Official MoneyPrinterTurbo skill: give it a topic or script and the agent installs, configures and produces a short video with voiceover, stock footage, subtitles and music; defaults to Chinese vertical MP4. Needs an LLM API key and a free Pexels key; macOS and Windows.

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.

Searches Reddit, X, YouTube, Hacker News, Polymarket and more in parallel for the past 30 days of discussion on a topic, scores it by engagement and summarizes it into a brief. Good for market research and meeting prep. Needs Python 3.12+; some sources need API keys.

Paid ads advisor: plans campaigns on Google Ads, Meta, LinkedIn, X and more, covering audience targeting, bidding and budgets, account diagnostics and ROAS/CPA optimization. From the marketingskills collection; needs no API key itself.

Helps subscription products reduce churn: designs cancellation flows, save offers and exit surveys, spots churn risk signals, and plans dunning and win-back emails after failed payments. For customer success, lifecycle and growth teams; billing platforms like Stripe need setup on your side.

Edits and refreshes existing marketing copy in seven sweeps: clarity, voice, value, proof, specificity, emotion and objection handling, keeping the meaning and author's voice. Can also audit and update stale pages. Complements the copywriting skill; from marketingskills.

Conversion rate optimization skill from the marketingskills collection: give it a homepage, landing page, pricing page or form and it diagnoses value proposition, headlines, CTAs, trust signals and friction, returning quick wins, high-impact changes, A/B test ideas and alternative copy.

Writes or rewrites marketing copy for homepages, landing pages, pricing pages and more: first clarifies page goals, audience and selling points, then produces headlines, value propositions and calls to action. From the marketingskills collection.

Marketing skill collection: 50 skills covering SEO audits, conversion optimization, landing page copy, pricing, paid ads, email and social media, all sharing a common product marketing context. Supports Claude Code, Codex and more.

AI search optimization (AEO/GEO) skill from the marketingskills collection: checks whether ChatGPT, Perplexity and Google AI Overviews cite your content and suggests rewrites and structure that AI can extract and cite more easily, including llms.txt and structured data.

Diagnoses website SEO issues: checks crawling and indexing, Core Web Vitals, metadata and on-page content, and gives prioritized, actionable fixes. From the marketingskills collection.

Teaches agents to use the Chrome DevTools MCP efficiently: snapshot first to get element uids, screenshot only when needed, paginate and filter large output, inspect CSS and test browser extensions. Needs chrome-devtools-mcp configured; maintained by the Chrome DevTools team.

Unified database lookup skill from K-Dense's scientific collection: reproducibly queries about 80 public database APIs such as PubChem, UniProt, ChEMBL, ClinicalTrials.gov and FRED, returning traceable results with endpoints, parameters and count checks. Some need API keys.