Skills
96,981 packaged capabilities and playbooks for agents. Install any of them with one command.
Testing & quality
Groups a git diff into review concerns and opens a local UI so humans can comprehend AI-generated code changes. Use when reviewing a PR, a branch diff, a turn diff, when a reviewed change has new commits, or when the user asks to run comprehende or to upload the report
Disciplined diagnosis loop for hard bugs and performance regressions. Reproduce → minimise → hypothesise → instrument → fix → regression-test. Use when user says "diagnose this" / "debug this", reports a bug, says something is broken/throwing/failing, or describes a performance regression.
Master end-to-end testing with Playwright and Cypress to build reliable test suites that catch bugs, improve confidence, and enable fast deployment. Use when implementing E2E tests, debugging flaky tests, or establishing testing standards.
Comprehensive ESLint agent for JavaScript/TypeScript code quality. Use when setting up ESLint, configuring linting rules, analyzing code for issues, fixing violations, or integrating ESLint into development workflows. Triggers on requests involving code quality, linting, static analysis, or ESLint configuration for JavaScript, TypeScript, React, or Node.js projects.
Improve AI application with evaluation-driven development. Define eval criteria, instrument the application, build golden datasets, observe and evaluate application runs, analyze results, and produce a concrete action plan for improvements. ALWAYS USE THIS SKILL when the user asks to set up QA, add tests, add evals, evaluate, benchmark, fix wrong behaviors, improve quality, or do quality assurance for any Python project that calls an LLM model.
Adversarial verification of finished work. Treats any "done" as a set of claims, then re-runs the claimed verifications, diffs what actually changed, detects weakened tests and false completion claims, and delivers an evidence-based verdict (VERIFIED / VERIFIED WITH CAVEATS / REFUTED). Use after any agent or model claims work is complete - "/fable-judge", "judge this work", "verify what it did", "did that actually work?". Also runs the fable-method trap suite against a skill or model via "/fable-judge suite <target>".
Use before claiming anything works, is fixed, is done, or passes; before status updates on changes you haven't run; before agreeing with someone else's claim about your work; and before state-changing commands like restarts, deletes, or config edits.
Execute native agentic ethical penetration testing and automated security audits against staging or authorized application targets. Discovers API logic flaws, BOLA/IDOR vulnerabilities, missing authentication, sensitive file exposures, and security misconfigurations within bounded scope. Produces verified security findings with reproduction PoCs and automatic Fable remediation work cards.
Audit and certify repository merge and release readiness against required quality gates, clean git working trees, and verified distribution artifacts. Use when preparing a release tag, validating release checklist criteria, publishing npm/PyPI packages, or certifying a branch for merge — even if the user does not explicitly say "fable-release" (e.g. "prepare the release", "is this ready to merge", "ship to production", "publish the package"). Do NOT use when verification is stale, failing, or missing (use fable-verify first).
Independently review git diffs against requested specifications, architectural invariants, and code standards, grounding findings in evidence. Use when reviewing pull requests, inspecting code changes before merge, auditing diffs for regressions, or performing pre-commit sanity reviews—even if the user doesn't explicitly say "fable-review" (e.g. "review this diff", "check this PR", "critique my changes", "code review this branch"). Do NOT use to implement fixes directly (use fable-tdd/fable-execute) or run tests (use fable-verify).
Launch, manage, and verify live applications across CLI binaries, web servers, TUIs, Electron apps, and background daemons with readiness probes and clean teardown. Use when starting development servers, executing live smoke tests, testing interactive CLI binaries, or driving runtime smoke verification — even if the user does not explicitly say "fable-run" (e.g. "start the dev server", "launch the app", "test the running CLI", "smoke test the web app"). Do NOT use for static analysis or unit testing without a running process (use fable-verify).
Verify complex code changes against independent mathematical oracles, derived specifications, headless browser environments, and isolated sandbox states. Use when deriving independent verification oracles, testing algorithms against reference models, verifying UI with headless browsers, or testing state transitions in sandboxes — even if the user does not explicitly say "fable-simulator" (e.g. "simulate this workflow", "verify with an independent oracle", "headless browser check", "derive a test oracle"). Do NOT use for simple unit test runs (use fable-verify).
Drive testable behavior changes and bug fixes through disciplined red-green-refactor cycles with observable regression tests. Use when implementing new features with unit/integration tests, fixing reproducible bugs, modifying business logic, or writing test-first behavior contracts — even if the user does not explicitly say "fable-tdd" (e.g. "fix this bug test-first", "write a test and make it pass", "add this feature with tests", "TDD this logic"). Do NOT use for broad exploratory prototyping without clear assertions (use fable-discover or fable-plan) or for post-implementation reviews (use fable-review).
Falsify software implementations and gather fresh, machine-checked acceptance proof across tests, builds, typechecks, and runtime smoke checks before completion. Use when running test suites, checking type correctness, validating acceptance criteria, or verifying post-mutation code integrity — even if the user does not explicitly say "fable-verify" (e.g. "verify my changes", "run all tests and typecheck", "check if everything passes", "prove this works"). Do NOT use for planning (use fable-plan) or diff code review (use fable-review).
Runs a structured PM design review against product requirements. Use when asked to review a Figma design, check a design against requirements, or assess whether a design meets the product spec. Produces a requirements coverage check, UX concerns, open questions, and an explicit approval status — approved, approved with conditions, or not approved.
Audit Figma MCP, design-to-code, code-to-canvas, canvas-editing, and design-system workflows for correctness, freshness, privacy, evidence, and routing quality. Use this skill when the user asks whether a Figma workflow, skill, task plan, MCP capability claim, or agent handoff is valid, current, safe, or production-ready.
Re-reads code you just wrote with fresh perspective to catch bugs, errors, and issues. Use after completing a feature, fixing a bug, or any code changes. Triggers on "review my code", "fresh eyes", "check for bugs", "did I miss anything", or "sanity check".
Turns an unfiled idea into a confirmed mini-spec, implements the selected approach, repeats code review and black-box testing, runs the project gate, and opens a draft pull request. Use when the user runs /implement-idea or asks to build something without an existing issue.
Review Kafka Connect connector configurations for common misconfigurations using the Lenses MCP server. Checks error handling, DLQ setup, converters, transforms, task count and task health. Use when user says "review connectors", "check connector configs", "why is my connector failing" or asks about Kafka Connect configuration. Do NOT use for creating, deploying or controlling connectors.
Write Minitest tests for Ruby and Rails applications. Use when creating test files, writing test cases, or testing new features. Not for RSpec — use rspec-coder instead. Covers both traditional and spec styles, fixtures, mocking, and Rails integration testing patterns.
Connect to Chrome Beta CDP with the agent-browser CLI to navigate pages, check data, and manipulate elements. Triggered by keywords such as "브라우저 확인", "페이지 봐줘", "DOM 확인", "데이터 점검", "클릭해줘", "화면 확인". Also used when confirming selectors or debugging execution failures while writing E2E scenarios. Runs standalone without an e2e/ folder.
Run a security and reliability health check on a Portaly Vibe payment integration before deployment. Trigger when the user mentions Portaly health check, payment security audit, pre-deploy check, sentry scan, callback verification audit, integration safety check, or wants to verify their Portaly payment integration is safe to go live.
Use when creating an approachable, self-contained HTML review aid for a pull request; explaining what changed, why it matters, how it works, and how it fits into the broader system; turning PR diffs, commits, tests, and architecture context into a local `.pr-review/` HTML page for reviewers; or helping reviewers understand complex code changes without dumping the full diff.
After pushing a PR and requesting review, keep tracking the review bot and CI. If the same subsystem still has findings requiring fixes after three consecutive rounds, audit the approach first; consult the user if there is disagreement about the direction.
Use when a Python change is about to be called done (before commit or PR) and whenever asked to review, audit, sanity-check, or clean up Python code or judge whether it meets standards. Also use at decision points the defaults cover: choosing retry/timeout/idempotency policy, config loading, pydantic placement, module boundaries, or a concurrency model.
Sets up static type checking for a Python package — choosing mypy, pyright, basedpyright or ty, strict configuration, per-module overrides, shipping py.typed — and fixes type-check errors. Use when the user says 'add type checking', 'set up mypy', 'pyright errors', 'make this package typed'. Not for lint or format failures, failing tests, runtime bugs, or the CI workflow that runs the checker.
This skill should be used when establishing comprehensive QA testing processes for any software project. Use when creating test strategies, writing test cases following Google Testing Standards, executing test plans, tracking bugs with P0-P4 classification, calculating quality metrics, or generating progress reports. Includes autonomous execution capability via master prompts and complete documentation templates for third-party QA team handoffs. Implements OWASP security testing and achieves 90% coverage targets.
Perform comprehensive code audits of Ruby on Rails applications based on thoughtbot best practices. Use this skill when the user requests a code audit, code review, quality assessment, or analysis of a Rails application. The skill analyzes the entire codebase focusing on testing practices (RSpec), security vulnerabilities, code design (skinny controllers, domain models, PORO with ActiveModel), Rails conventions, database optimization, and Ruby best practices. Outputs a detailed markdown audit report grouped by category (Testing, Security, Models, Controllers, Code Design, Views) with severity levels (Critical, High, Medium, Low) within each category.
React performance optimization guidelines from Vercel Engineering. This skill should be used proactively when writing, reviewing, or refactoring React code to ensure optimal performance patterns. Triggers on tasks involving React components, bundle optimization, or performance improvements.
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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.