Skills real projects publish on GitHub, most starred first. Each one says what it will make an agent do before you copy it.
langgeniusSkilllanggenius/dify/.agents/skills/frontend-testing/SKILL.md
Use when writing or changing Vitest or React Testing Library tests under `web/` or `packages/dify-ui/`, or when the user explicitly requests frontend test strategy, including evaluation of an existing strategy. Do not use for frontend code-review-only requests, general testability discussion, Python tests, or Cucumber/Playwright E2E.
BlushyesSkillBlushyes/reef/.agents/skills/testing-reef/SKILL.md
Conventions and gotchas for writing tests in the reef Rust workspace — unit, integration, property, snapshot, benchmark, and fuzz. Use whenever adding or modifying a test in reef or test-support, or when the user asks "add a test for X", "how should I test Y", "why is this test flaky", "where does this test go", or anything about test fixtures, snapshots, proptest, or CI test failures. Also use when touching clock/time code (requires splitting `*_at(now, t)` helpers), or any code that mutates `cwd`/`HOME` (needs process-wide lock). Covers file-placement rules, the `test-support` fixture crate, insta filters, proptest strategy construction, and the specific pitfalls we've paid for in production — macOS tempdir symlinks, env-var sharing across parallel tests, and the HOME-redirect pattern for prefs-reading code.
rusel95Skillrusel95/ios-agent-skills/skills/ios-testing/SKILL.md
Invoke any time a user is writing iOS/Swift tests or asking why tests behave a certain way — including XCTest versus Swift Testing (@Test/#expect) choices, async ViewModel tests with @Observable or @Published, snapshot testing across device sizes, mocking protocols for dependency injection, setUp/tearDown lifecycle issues, tests that fail on CI but pass locally, flaky async tests, testing VIPER/TCA/MVVM architectures, and coverage gaps on error paths. The trigger is user intent: they are trying to verify, assert, or validate iOS/Swift behavior in a test context, whether they use the word 'testing' or not.
caliber-ai-orgSkillcaliber-ai-org/ai-setup/.agents/skills/caliber-testing/SKILL.md
Writes Vitest tests following project patterns: __tests__/ directories, vi.mock() for module mocking with vi.hoisted() for test-time factories, global LLM mock from src/test/setup.ts, environment variable save/restore in beforeEach/afterEach, vi.clearAllMocks() lifecycle, and test file organization. Use when user says 'write tests', 'add test coverage', 'test this', creates *.test.ts files, or when test failures appear in CI. Do NOT use for non-test code or for debugging without writing tests.
caliber-ai-orgSkillcaliber-ai-org/ai-setup/.claude/skills/caliber-testing/SKILL.md
Writes Vitest tests following project patterns: __tests__/ directories, vi.mock() for module mocking with vi.hoisted() for test-time factories, global LLM mock from src/test/setup.ts, environment variable save/restore in beforeEach/afterEach, vi.clearAllMocks() lifecycle, and test file organization. Use when user says 'write tests', 'add test coverage', 'test this', creates *.test.ts files, or when test failures appear in CI. Do NOT use for non-test code or for debugging without writing tests.
ag-ui-protocolSkillag-ui-protocol/ag-ui/.github/skills/agui-dotnet-unit-tests/SKILL.md
Author unit tests for the AG-UI .NET SDK (the *.UnitTests projects), following the SDK's serialization and compatibility conventions. USE FOR: adding unit-test coverage for a new type/method in AGUI.Abstractions/Formatting/Protobuf/Client/Server, event serialization round-trips, JsonDocument property-name assertions, backward-compatibility fixtures against TypeScript JSON, protobuf codec round-trips, client builder/handler tests, server ChatResponseUpdate conversion tests, SSE formatter tests. DO NOT USE FOR: HTTP pipeline / WebApplicationFactory end-to-end tests (use the agui-dotnet-integration-tests skill), cross-language TS↔C# server-parity tests (use the cross-language test skill).
MongoDBSkillmongodb/docs/.claude/skills/grove-test/SKILL.md
Create or fix tests for existing Grove code examples. Use when the user asks to "add a test", "create a test", "fix this test", "update the test", "the test doesn't match the output", "test is failing", or wants to add test coverage for an existing example or fix a broken test.
MicrosoftSkillmicrosoft/testfx/.agents/skills/test-smell-detection/SKILL.md
Deep-dive audit using the full testsmells.org 19-smell academic catalog for tests in any language. Every finding maps to a named, citable smell from the research literature (Assertion Roulette, Duplicate Assert, Mystery Guest, Eager Test, Sensitive Equality, Conditional Test Logic, Sleepy Test, Magic Number Test, etc.) with research-backed severity. Polyglot: .NET (MSTest/xUnit/NUnit/TUnit), Python (pytest/unittest), TS/JS (Jest/Vitest/Mocha/node:test), Java (JUnit/TestNG), Go, Ruby (RSpec/Minitest), Rust, Swift, Kotlin (JUnit/Kotest), PowerShell (Pester), C++ (GoogleTest/Catch2). INVOKE ONLY when explicitly asked for the testsmells.org 19-smell academic catalog or citable smell names from the literature. DO NOT USE FOR: general or pragmatic audits — use test-anti-patterns; writing new tests (use code-testing-agent, or writing-mstest-tests for MSTest); running tests (use run-tests); framework migration.
silo-codeSkillsilo-code/silo/.agents/skills/silo-testing/SKILL.md
Use when writing or updating unit tests in the Silo repo. Covers the co-located Vitest setup, the pure-logic (no @testing-library/react) style and how to extract testable helpers, driving host state directly via the valtio store, and the contract-and-edges coverage expectations.
jdanigoSkilljdanigo/hydraia/skills/e2e-testing/SKILL.md
Use when writing or maintaining end-to-end tests — Playwright (preferred) or Cypress critical-flow suites. Pattern playbook: page objects, stable selectors, fixtures and isolation, condition-based waiting, flaky quarantine, CI wiring. Backs the e2e-runner agent.
cosmixSkillcosmix/loom/skills/loom-testing/SKILL.md
Test implementation across unit, integration, e2e, security, infrastructure, data pipeline, and ML domains.
OpenClaudiaSkillOpenClaudia/openclaudia-skills/skills/ab-test-setup/SKILL.md
Design, plan, and analyze A/B tests with statistical rigor. Use when the user asks about A/B testing, split testing, experiment design, statistical significance, sample size calculation, test duration, multivariate testing, or conversion experiments. Trigger phrases include "A/B test", "split test", "experiment", "statistical significance", "sample size", "test duration", "which version wins", "conversion experiment", "hypothesis test", "variant testing".
AnnenkovLabsSkillAnnenkovLabs/girl-agent/.agents/skills/testing-webui/SKILL.md
Test the girl-agent WebUI end-to-end locally. Use when verifying profile setup, profile selection, config, assistant, addons, logs, memory, and runtime controls.
Prisma-Labs-DevSkillPrisma-Labs-Dev/apple-skills/skills/swift-testing/SKILL.md
API reference: Swift Testing framework. @Test, @Suite, #expect, #require, traits, parameterized tests, migrating from XCTest.
MicrosoftSkillmicrosoft/testfx/.agents/skills/test-anti-patterns/SKILL.md
Audits existing test code in any language for anti-patterns and quality issues — produces a severity-ranked report (Critical / Warning / Info) with concrete code-level fixes. Polyglot: .NET (MSTest/xUnit/NUnit/ TUnit), Python (pytest/unittest), TS/JS (Jest/Vitest/Mocha/node:test), Java (JUnit/TestNG), Go, Ruby (RSpec/Minitest), Rust, Swift, Kotlin (JUnit/Kotest), PowerShell (Pester), C++ (GoogleTest/Catch2). INVOKE when asked to audit, review, rank, or find problems in existing tests — "audit my tests", "test smell audit", "rank by severity", tests that pass but verify nothing, no/missing assertions, swallowed exceptions, always-true / self-comparing / tautological assertions, broad exception types, flakiness (sleep/Date.now/time.sleep), ordering dependency, shared global state, duplicated tests, magic values, missing await on async assertions. DO NOT USE FOR: writing new tests (use code-testing-agent, or writing-mstest-tests for MSTest); running tests (use run-tests); framework migration.
SentrySkillgetsentry/sentry-java/.claude/skills/test/SKILL.md
Run tests for a specific SDK module. Use when asked to "run tests", "test module", "run unit tests", "run system tests", "run e2e tests", or test a specific class. Auto-detects unit vs system tests. Supports interactive mode.
LambdaTestSkillLambdaTest/agent-skills/flutter-testing-skill/SKILL.md
Generates Flutter widget tests, integration tests, and golden tests in Dart. Supports local execution and TestMu AI cloud for real device testing. Use when user mentions "Flutter", "widget test", "WidgetTester", "testWidgets", "flutter_test", "integration_test". Triggers on: "Flutter", "widget test", "Dart test", "testWidgets", "WidgetTester", "golden test".
openvettaSkillopenvetta/open-vetta/.agents/skills/vetta-testing/SKILL.md
为 OpenVetta 的功能变更、Bug 修复、重构、公共合同和 UI 交互设计、编写或审查测试；在决定测试范围、补充回归测试、覆盖用户常见使用流程或评估测试质量时使用。纯文档或没有运行时行为变化的编辑不使用。
MicrosoftSkillmicrosoft/testfx/.agents/skills/grade-tests/SKILL.md
Grades a specified set of test methods individually and produces a concise table mapping each test (fully-qualified name) to a letter grade (A–F), a score band, pseudo-mutation resilience, a one-line note, and a concrete improvement for every grade below A — designed to be posted as a PR comment. Use when the caller wants per-test feedback on a curated list of methods (for example, the new or modified tests in a pull request), not a suite-wide audit. Polyglot: .NET (MSTest/xUnit/NUnit/TUnit), Python (pytest/unittest), TS/JS (Jest/Vitest/Mocha/node:test), Java (JUnit/TestNG), Go, Ruby (RSpec/Minitest), Rust, Swift (XCTest/Swift Testing), Kotlin (JUnit/Kotest), PowerShell (Pester), C++ (GoogleTest/Catch2/doctest). Input is a list of test methods (or method bodies / file+line spans); output is a compact markdown table plus a short summary. DO NOT USE FOR: full suite audits (use test-quality-auditor agent or test-anti-patterns), writing new tests (use code-testing-generator agent or writing-mstest-tests), fixing failures, or measuring code coverage.
mattgierhartSkillmattgierhart/PRD-driven-context-engineering/.claude/skills/prd-v07-test-planning/SKILL.md
Define test cases BEFORE implementation, ensuring every API, business rule, and user journey has verifiable acceptance criteria during PRD v0.7 Build Execution. Triggers on requests to define tests, plan test coverage, create test cases, or when user asks "define tests", "test planning", "what to test?", "test cases", "test coverage", "TEST-", "test-first". Consumes EPIC- (scope), API-, DBT-, BR-, UJ-. Outputs TEST- entries with Given-When-Then format. Feeds v0.7 Implementation Loop.
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