Skills
97,222 packaged capabilities and playbooks for agents. Install any of them with one command.
Testing & quality
Enforces the project's core TypeScript standards, including explicit typing, import organization, class member ordering, and code safety rules. ALWAYS apply when creating, modifying, or reviewing any TypeScript (.ts/.tsx) file.
Find out why the tests pass but the app is broken. Catches false greens: a green suite over a feature that does not work, a mocked API standing in for a real one, an assertion that holds no matter what the app does, a click handler wired to nothing. Use when the suite is green and the user says it is broken, when a test never fails, when coverage looks fine but bugs still ship, or before trusting a passing run you did not watch.
Read-only automated QA sweep of a deployed stardust site on AEM Edge Delivery Services — validates routing, content fidelity vs the source capture, template conformance, rendered integrity (geometry, JS errors, broken images), visual regression vs baselines, metadata/SEO/JSON-LD, link integrity, accessibility (axe), and performance budgets, then emits a findings report with an allowlist for documented non-defects. Finds issues; never fixes them. Use when the user asks to "QA the site", "validate the migration", "check the live site for issues", "run a QA sweep/regression check", or invokes `$stardust qa` (`/stardust:qa` in Claude Code) <live-url>.
Storybook 10 testing patterns with Vitest integration, ESM-only distribution, CSF3 typesafe factories, play() interaction tests, Chromatic TurboSnap visual regression, module automocking, accessibility addon testing, and autodocs generation. Use when writing component stories, setting up visual regression testing, configuring Storybook CI pipelines, or migrating from Storybook 9.
Frontend full-chain performance optimization guide based on Web Vitals metrics. Provides metric thresholds, diagnostic methods, and optimization strategies for LCP, FCP, INP, CLS, TTFB, TBT. Use when optimizing frontend performance, analyzing Web Vitals, reducing page load time, fixing layout shifts, improving interaction responsiveness, or reviewing frontend code for performance issues.
Generates Gauge test specifications in Markdown with step implementations in Java, Python, JS, or Ruby. ThoughtWorks' test automation framework. Use when the user mentions "Gauge", "spec file", "## Scenario", or "step implementation". Triggers on: "Gauge", "Gauge spec", "Gauge framework", "ThoughtWorks test".
Survey a codebase's animation and motion code as a senior motion advisor, then produce a prioritized audit and self-contained implementation plans for other agents (or cheaper models) to execute. Read-only on source code — it plans improvements, it does not apply them. Use when the user asks to "improve the animations", "audit the motion", "make this app feel better", or wants a roadmap of animation fixes rather than a review of a single diff.
Audit Android Jetpack Compose repositories for performance, animation phase correctness, state management, side effects, composable API quality, and adjacent Android launch UX resource risks such as blurry Android 12+ splash icons. Scans source code, scores each category from 0-10, writes a strict markdown report, and summarizes the most important fixes. Use when reviewing a Compose codebase, rating repository quality, inspecting recomposition/state issues, animation issues, or running a Compose audit.
This skill should be used when the user asks to “pentest SSH services,” “enumerate SSH configurations,” “brute force SSH credentials,” “exploit SSH vulnerabilities,” “perform SSH tunneling,” or “audit SSH security.” It provides comprehensive SSH penetration testing methodologies and techniques.
Integrate any number of feature branches from parallel worktrees through one safe integration branch, validating after each merge and running the project's full check suite before touching the main line. Use when parallel worktree development is done and the branches need to be merged, or when the user says "merge my worktrees", "integrate these branches", or invokes /worktree-merge.
Validates animation durations, enforces typography scale, checks component accessibility, and prevents layout anti-patterns in Tailwind CSS projects. Use when building UI components, reviewing CSS utilities, styling React views, or enforcing design consistency.
Emulated GitHub REST API for local development and testing. Use when the user needs to interact with GitHub API endpoints locally, test GitHub integrations, emulate repos/issues/PRs, set up GitHub OAuth flows, configure GitHub Apps, test webhooks, or work with actions/checks without hitting the real GitHub API. Triggers include "GitHub API", "emulate GitHub", "mock GitHub", "test GitHub OAuth", "GitHub App JWT", "local GitHub", or any task requiring a local GitHub API.
Jest best practices, patterns, and API guidance for JavaScript/TypeScript testing. Covers mock design, async testing, matchers, timer mocks, snapshots, module mocking, configuration, and CI optimization. Baseline: jest ^30.5.2. Triggers on: jest imports, describe, it, test, expect, jest.fn, jest.mock, jest.spyOn, mentions of "jest", "unit test", "test suite", or "mock".
Expert guidance for writing fast, maintainable Minitest tests in Rails applications. Use when writing tests, converting from RSpec, debugging test failures, improving test performance, or following testing best practices. Covers model tests, policy tests, request tests, system tests, fixtures, and TDD workflows.
PR review using parallel specialized agents for code quality, security, testing, architecture, and performance analysis. Synthesizes findings into a review report with conventional comments (praise/issue/suggestion/nitpick) and approve or request-changes verdict. Use when reviewing pull requests, conducting security audits, or validating changes before merge.
Use when the user asks to create, write, generate, modify, update, fix, or validate an API Governance ruleset (Validation Profile). Covers governance rules for OpenAPI, RAML, AsyncAPI, MCP servers, Anypoint API instances, and API projects. Trigger phrases include “governance ruleset,” “validation profile,” “governance rule,” “API conformance,” “enforce policy,” “create ruleset,” and “validate ruleset.”
Audit external compatibility between two DSH (DeepSeek Harness) versions and detect reverts, producing an upgrade-report directory. Compare git tags with a source checkout, or published npm packages without one. Use whenever the user asks to check, compare, or audit two DSH versions or whether upgrading is safe—for example, “more changes or reverts in dsh-vX -> dsh-vY” or “compare the breaking changes”—even with only two version numbers and no source location. Read-only outside the report directory; npm mode installs in isolation with --ignore-scripts.
Validate simulations across three stages — run pre-flight checks on configuration files (parameter ranges, required fields, disk space), monitor runtime logs for residual growth, NaN/Inf, and adaptive dt collapse, and perform post-flight validation of results (physical bounds, mass/energy conservation, convergence). Diagnose failed simulations with probable-cause analysis and recommended fixes. Use when preparing to launch a simulation, checking whether a running job is healthy, verifying that finished results are trustworthy, or debugging a crash or blow-up, even if the user only says "my simulation crashed" or "can I trust these results."
Black-box CLI grading harness that runs a test suite against a target CLI and reports per-rule pass/fail results from the cli-for-agents 45-rule catalog. Use when reviewing, auditing, or grading a command-line tool for agent-friendliness. Trigger even if the user doesn't explicitly say "agent-friendly"—apply whenever they ask "is my CLI good for agents?", "review this CLI", "grade my CLI against the rules", "check if this tool is safe to automate", or "audit command-line design". Companion to the cli-for-agents distillation skill.
Python code quality anti-patterns and review checks: exception hierarchy correctness, singleton identity comparison, narrow exception handling, wildcard import avoidance, magic number naming, and dead local removal. Use when reviewing or self-reviewing Python code for correctness and readability defects that linters and reviewers should catch.
Investigate and fix CI failures on a pull request. Use when CI checks fail on a PR branch — covers finding the PR, identifying failed checks, downloading logs and artifacts, extracting the failure cause, and iterating on a fix. Requires the `gh` CLI.
Run technical quality checks on an existing deck. Finds and fixes font size violations, shape overlaps, contrast issues, missing sources, and layout compliance problems. Use when the user says “check the deck for issues”, “run QA”, “lint the slides”, “are there any formatting problems”, “audit the presentation”, or wants to verify visual quality before sharing.
Dodo Payments test mode and production launch, covering test cards and payment methods, success and decline scenarios, renewal simulation, local webhook testing with the CLI, copying products from test to live, and a go-live checklist. Use when verifying payment flows, switching from test_mode to live_mode, or preparing to launch
Use when writing unit tests, adopting Swift Testing framework, making tests run faster without simulator, architecting code for testability, testing async code reliably, or migrating from XCTest - covers @Test/@Suite macros, #expect/#require, parameterized tests, traits, tags, parallel execution, host-less testing
Perform spatial and temporal convergence analysis for solution verification — compute observed convergence orders from grid or timestep refinement studies, apply Richardson extrapolation to estimate discretization error, and calculate the Grid Convergence Index (GCI) per ASME V&V 20 standards. Use when verifying that a numerical solution converges at the expected rate, estimating the error on the finest mesh, checking whether grids are in the asymptotic range, or preparing formal verification reports, even if the user only asks “is my mesh fine enough” or “how accurate is my solution”
ALWAYS use when diagnosing Ably issues — messages not arriving, presence not updating, connection failures, auth errors (40101, 40142, 40160), channel lifecycle problems, push notification issues, Chat room issues, Spaces member/cursor issues, or any Ably error code. Provides Ably CLI commands to observe live traffic, inspect state, and simulate clients. Not for building new Ably integrations (use using-ably skill instead).
New to MCP?
From what the protocol is to installing your first server, these answers cover most first questions.
An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.