Agent skills you can check before you install
Public SKILL.md skills from GitHub repositories with 50+ stars and from the vendors themselves, scanned and scored. Install any of them with one command in Claude Code, Cursor, Codex, GitHub Copilot or Gemini CLI.
14,533 skills from 417 repositories · updated 15 hours ago
892 skills
- mirrord-chaosmetalbear-co/mirrordHelp users chaos test their app with mirrord: inject artificial latency or connection errors into a mirrord session's outgoing traffic via per-session chaos rules managed with the `mirrord chaos` CLI. Use when a user wants to add latency or delay to outgoing connections or a dependency (e.g. a slow database), simulate connection failures (reset, timed out, refused), test app behavior under degraded network conditions, or wire chaos rules into CI test runs. Always use this skill instead of the deprecated _experimental_.latency mirrord config option.TestingNo warnings★ 5.4K↓ —
- hunt-corselementalsouls/Claude-BugHunterHunt CORS Misconfiguration — origin-reflection with credentials, null-origin trust, subdomain-regex bypass (unanchored vs unescaped-dot vs prefix-only), pre-flight (OPTIONS) gating bypass, postMessage origin checks. High only when an attacker-controlled origin can perform a CREDENTIALED cross-origin read of sensitive data and you have proven it in a browser. Use when testing API endpoints, SPAs, or any app emitting Access-Control-* headers.TestingNo warnings★ 5.2K↓ —
- scaffold-dotnet-test-projectdotnet/skillsMUST USE when an existing .NET test project was excluded from a .slnf/CI solution filter, disappeared from .sln/.slnx discovery, or lost its production ProjectReference; also for requests to set up, create, reuse, add, register, include, or repair a test project. Handles "tests pass directly but CI discovers zero", exact solution wiring, xUnit/NUnit/MSTest, and central packages. DO NOT USE to only author tests in an already-wired project (code-testing), run tests, migrate, or correct MSTest syntax/configuration without changing project or CI files (writing-mstest-tests).TestingNo warnings★ 5.7K↓ —
- exp-test-maintainabilitydotnet/skillsDetects duplicate boilerplate, copy-paste tests, and structural maintainability issues across .NET test suites. Use when the user asks to reduce repetition, consolidate similar test methods, convert copy-paste tests to data-driven parameterized tests, suggest a better test structure, or identify refactoring opportunities. Identifies repeated construction, assertion patterns, copy-paste methods convertible to DataRow/Theory/TestCase, redundant setup/teardown, and shared infrastructure. Produces an analysis report with concrete before/after suggestions. Works with MSTest, xUnit, NUnit, and TUnit. DO NOT USE FOR: writing new tests (use writing-mstest-tests), reviewing test quality or anti-patterns (use test-anti-patterns), or deep mock auditing (use exp-mock-usage-analysis).TestingNo warnings★ 5.7K↓ —
- assertion-qualitydotnet/skillsAnalyze assertion quality, depth, variety, and false confidence in existing tests. ALWAYS USE when asked about weak, shallow, trivial, always-true, self-referential, assertion-free, presence/truthiness-only, or insufficiently diverse assertions, including MSTest, Jest, pytest, and Go. DO NOT USE for direct fixes: writing-mstest-tests owns supplied MSTest assertions; code-testing owns new cases. Use test-gap-analysis when asked whether tests would catch a production change, and test-anti-patterns for general severity-ranked audits.TestingNo warnings★ 5.7K↓ —
- testability-obstacledotnet/skillsMUST USE for C#/.NET deterministic tests that require the smallest production seam for DateTime/Task.Delay/File/Environment/Guid/Random, static API preservation, nested/parallel overrides, or no real I/O. USE ONLY when the target workspace contains C# source plus a .csproj or .sln. DO NOT USE for audits, bulk migration, code that already has an injectable seam, or an explicit migration to a user-named existing abstraction (migrate-static-to-wrapper). Use instead of general test generation when the requested test is impossible without a production edit and seam selection is still open.TestingNo warnings★ 5.7K↓ —
- migrate-mstest-v1v2-to-v3dotnet/skillsUse this skill before answering or editing whenever an MSTest v1/v2 project is being upgraded or repaired for v3. Triggers include QualityTools assembly references; MSTest.TestFramework/TestAdapter 1.x-2.x; "upgrade to MSTest v3"; comparing v1 and v2 migration paths; choosing MSTest or MSTest.Sdk; CS0411/CS1503 after a v3 package bump; DataRow type mismatch, MSTEST0014, or "Test data doesn't match method parameters"; .testsettings/LegacySettings to .runsettings; timeout changes; and net5.0 or other dropped v3 TFMs. Still use it when packages say 3.x but migration source errors or legacy settings remain. Preserve VSTest/MTP. Do not use for a clean v3 project, v3-to-v4, framework conversion, or runner-only migration.TestingNo warnings★ 5.7K↓ —
- maui-dependency-injectiondotnet/skillsGuidance for configuring dependency injection in .NET MAUI apps — service registration in MauiProgram.cs, lifetime selection (Singleton / Transient / Scoped), constructor injection, Shell navigation auto-resolution, platform-specific registrations, and testability patterns. USE FOR: "dependency injection", "DI setup", "AddSingleton", "AddTransient", "AddScoped", "service registration", "constructor injection", "IServiceProvider", "MauiProgram DI", "register services", "BindingContext injection". DO NOT USE FOR: data binding (use maui-data-binding), Shell route configuration (use maui-shell-navigation), unit-test mocking frameworks (use standard xUnit and NSubstitute patterns).TestingNo warnings★ 5.7K↓ —
- migrate-xunit-to-xunit-v3dotnet/skillsMigrate .NET test projects from xUnit.net v2 to xunit.v3 and fix v3 breaks. Use for package/CPM conversion, OutputType=Exe, preserving the VSTest or MTP runner (including projects currently using YTest.MTP.XUnit2), incompatible TFMs, async void tests, string-to-Type attributes, custom Fact/Theory/BeforeAfterTest attributes, Xunit.SkippableFact, xunit.abstractions/extensibility consolidation, and Xunit.Combinatorial/StaFact compatibility. Do not use for framework conversion or a runner-only migration. For xUnit v3 MTP filter syntax, also use migrate-vstest-to-mtp.TestingNo warnings★ 5.7K↓ —
- redteam-mindsetelementalsouls/Claude-BugHunterRed-team operator discipline — the mindset corrections that separate offensive testing from defensive WAPT. Built from authorized red-team work where conservative defaults caused multiple findings to be missed and one to be incorrectly retracted. Use at the START of any red-team engagement and again whenever feeling stuck or considering "stopping" on a defended target. The single most important skill to load when scope is "external red team" not "bug bounty / WAPT".TestingNo warnings★ 5.2K↓ —
- test-driven-devzebbern/claude-code-guideTest-driven development with red-green-refactor loop. Use when user wants to build features or fix bugs using TDD, mentions "red-green-refactor", wants integration tests, or asks for test-first development.TestingNo warnings★ 4.7K↓ —
- mvpdavepoon/buildwithclaudeGuides the founder through designing and optionally building the simplest MVP or prototype that validates their current hypotheses. Use when the founder wants to build something to test assumptions, discusses what to build next, wants to interpret results from a live MVP, or is deciding whether the current approach is still right. Also use when a founder proposes something to build — the skill will check whether the proposed form is the simplest thing that generates honest signal.TestingNo warnings★ 3.7K↓ —
- hatch-petnexu-io/open-designCreate, repair, validate, preview, and package Codex-compatible animated pet spritesheets from character art, screenshots, generated images, or visual references. Use when a user wants to hatch a Codex pet, create a custom animated pet, or build a built-in pet asset with an 8x9 atlas, transparent unused cells, row-by-row animation prompts, QA contact sheets, preview videos, and pet.json packaging. This skill composes the installed $imagegen system skill for visual generation and uses bundled scripts for deterministic spritesheet assembly.TestingNo warnings★ 103.2K↓ —
- ops-settingsdavepoon/buildwithclaudePost-setup credential manager. Shows current integration status (configured/missing/expired) and lets you update individual credentials without re-running the full setup wizard. Runs a smoke test after each update.TestingNo warnings★ 3.7K↓ —
- corevercel-labs/agent-browserCore agent-browser usage guide. Read this before running any agent-browser commands. Covers the snapshot-and-ref workflow, navigating pages, interacting with elements (click, fill, type, select), extracting text and data, taking screenshots, managing tabs, handling forms and auth, waiting for content, running multiple browser sessions in parallel, and troubleshooting common failures. Use when the user asks to interact with a website, fill a form, click something, extract data, take a screenshot, log into a site, test a web app, or automate any browser task.OfficialTestingNo warnings★ 44.4K↓ —
- gemininowork-studio/notfair-pluginCross-model second opinion from Google Gemini — a different AI reviewing the same changes, with deep Google ecosystem knowledge. Three modes: review (pass/fail gate for Google Ads campaigns, SEO metadata, or code), challenge (adversarial stress-test that tries to break your changes), and consult (open Q&A with Gemini on Google Ads strategy, SEO best practices, or implementation questions). Use when the user says "gemini review", "ask gemini", "gemini challenge", "second opinion from gemini", "consult gemini", "stress test with gemini", "what would gemini say", "cross-model review", or "get another opinion". Voice aliases: "gem", "gemini check". Especially useful for Google Ads changes, SEO metadata updates, campaign structure decisions, keyword strategies, and bid/budget changes — Gemini has native Google ecosystem knowledge that complements Claude's analysis.TestingNo warnings★ 4K↓ —
- red-handed-auditdavepoon/buildwithclaudeCheck whether the tests the agent said passed actually ran. Reads the Claude Code session transcript and git state locally, then reports each gap with a timestamp and the quoted line. No model calls, nothing leaves the machine.TestingNo warnings★ 3.7K↓ —
- offensive-lateral-movementSnailSploit/Claude-RedComprehensive lateral movement tradecraft for authorized red team engagements covering credential-based movement (pass-the-hash, pass-the-ticket, overpass-the-hash), NTLM relay attacks (ntlmrelayx with PetitPotam, DFSCoerce, PrinterBug coercion), remote execution protocols (WMI, WinRM, DCOM, PsExec and alternatives), RDP session hijacking, and network pivoting through tunneling tools (chisel, ligolo-ng, SSH tunnels, SOCKS proxies). Provides operator-ready command sequences for mimikatz, crackmapexec/netexec, impacket suite, and evil-winrm with emphasis on OPSEC considerations, SMB signing bypass, and detection evasion. Maps to MITRE ATT&CK T1021 (Remote Services), T1550 (Use Alternate Authentication Material), and sub-techniques. Includes defender-perspective detection guidance for blue team awareness and a rapid engagement cheatsheet for common lateral movement scenarios encountered during internal penetration tests and assumed-breach exercises.TestingNo warnings★ 7.8K↓ —
- offensive-deauth-disassocSnailSploit/Claude-RedDeauthentication and disassociation attacks against 802.11 networks — targeted single-client deauth for handshake capture, broadcast deauth for DoS (with authorization), action-frame attacks bypassing 802.11w (PMF), beacon flooding, mdk4 / aireplay-ng tooling, and rate-limit / PMF-aware operation. Use to coerce client reconnection (handshake capture, evil-twin roaming), as targeted DoS, or to test PMF posture.TestingNo warnings★ 7.8K↓ —
- offensive-network-attacksSnailSploit/Claude-RedDense description covering ARP spoofing, LLMNR/NBT-NS/mDNS poisoning, DNS poisoning, MITM attacks, VLAN hopping, DHCP attacks, 802.1X/NAC bypass, IPv6 attacks. Tools: Bettercap, Responder, mitm6, Ettercap, Wireshark. MITRE T1557, T1040. Use when conducting internal network assessments or testing Layer 2/3 attack surface.TestingNo warnings★ 7.8K↓ —
- offensive-sstiSnailSploit/Claude-RedDense description covering Server-Side Template Injection across Jinja2, Twig, Freemarker, Velocity, Pebble, Smarty, Mako, Handlebars, ERB, Thymeleaf, EJS, Pug. Engine fingerprinting, filter bypass, blind exploitation, WAF evasion, SSTI-to-RCE chains. Tools: tplmap. CWE-1336. MITRE T1190. Use when testing template rendering endpoints or exploiting template injection for code execution.TestingNo warnings★ 7.8K↓ —
- semgrep-rule-variant-creatortrailofbits/skillsCreates language variants of existing Semgrep rules. Use when porting a Semgrep rule to specified target languages. Takes an existing rule and target languages as input, produces independent rule+test directories for each language.TestingNo warnings★ 7.7K↓ —
- testing-handbook-generatortrailofbits/skillsGenerates Claude Code skills from the Trail of Bits Testing Handbook (appsec.guide), analyzing handbook pages and emitting SKILL.md files with the structure each skill type requires. Use when creating or refreshing a skill from handbook content, or when the user names the testing handbook or appsec.guide. Not for answering security testing questions — the generated skills cover those.TestingNo warnings★ 7.7K↓ —
- constant-time-testingtrailofbits/skillsMeasures timing side channels in cryptographic implementations by running them, using dudect for statistical analysis and Timecop over Valgrind for dynamic tracing. Covers the formal, symbolic, dynamic, and statistical tool categories and how to read a result. Use when testing whether a running implementation is constant-time, measuring timing variance on a compiled binary, or investigating a suspected timing attack. Not for statically inspecting compiler output — the constant-time-analysis plugin covers that.TestingNo warnings★ 7.7K↓ —