Pure-reference catalog of the testing categories that apply to a video-game build before it ships. Defines the six canonical buckets the industry tests against - functional / compliance / compatibility / performance / localization / accessibility - plus the multiplayer and content-rating sub-axes. Cross-references each bucket to the platform-holder vocabulary that drives it (Microsoft Xbox Requirements / XR test cases, Sony TRC, Nintendo Lotcheck, Steam Direct review). Use as the taxonomy lookup when planning a game test pass, scoping QA effort, mapping platform-cert findings back to internal test categories, preparing a submission checklist, reviewing first-party certification requirements, or triaging cert testing failures against internal categories.

Pure-reference catalog of hardware-in-the-loop (HIL) testing for embedded systems. Defines the HIL pattern (ECU-under-test + real-time plant simulator + I/O cards emulating sensors / actuators / buses), the V-cycle progression (MIL → SIL → PIL → HIL), the canonical vendor stack (NI VeriStand + PXI / CompactRIO, dSPACE SCALEXIO / MicroAutoBox, Vector CANoe + VT System, Speedgoat real-time targets), bus emulation per protocol (CAN / CAN FD / LIN / FlexRay / Automotive Ethernet / SOME-IP), fault-injection patterns (short-to-ground, open-circuit, signal corruption), DO-178C / ISO 26262 / IEC 61508 alignment, and the test-evidence chain HIL produces. Use as the HIL terminology + vendor + standard reference when scoping an embedded test rig or interpreting an automotive / aerospace / industrial HIL test report.

Build a trace specification document per feature - defines the trace shape (root span + child spans + key attributes per OpenTelemetry semantic conventions) that production code MUST emit. The spec drives both implementation reviews AND trace-assertion tests, so a single declarative document is the source of truth for what observability "looks like" for a feature. Use before instrumenting a new feature, when existing spans have grown organically with no agreed shape, or after an incident where a debugging session stalled on missing span attributes.

Validates OpenTelemetry Collector pipeline configurations and verifies spans flow end-to-end through the collector: runs `otelcol validate --config`, wires the `debug`/`file` exporter for span-output assertions, and integrates the full cycle into CI. Use when a collector config change (new receiver, processor swap, exporter wiring) needs correctness verification before deployment.

Authors and runs Windows UI tests against WinAppDriver, Microsoft's W3C-WebDriver service for UWP / WPF / WinForms / Win32 apps: installing + launching `WinAppDriver.exe` on `127.0.0.1:4723`, declaring `app` / `platformName` / `appArguments` / `appTopLevelWindow` capabilities, finding elements by `AccessibilityId` / `Name` / `ClassName`, and Windows-runner CI. Use when driving a native Windows app from a Selenium-style client (C#, Java, Python, Ruby, JS); for the actively-maintained Appium 2.x wrapper over the same server use appium-windows-driver, for a C#-only FlaUI client use flaui-tests, and to choose among Windows desktop drivers first use desktop-test-strategy-reference.

Jira Cloud bug workflow runner using the REST API v3: issue creation with an ADF description, runtime transition lookup and apply, JQL search for triage queues and duplicate detection, severity/priority field updates, label-based classification (severity/priority/regression), and idempotent CI-driven filing from JUnit XML test failures. Use when the target tracker is Jira Cloud and the task involves Jira lifecycle states (create, triage, transition, close). Distinct from a platform-agnostic event-driven CI defect filer, and from linear-bug-workflow-runner / github-issues-bug-workflow for other trackers.

Authors Great Expectations (GX Core) ExpectationSuites, builds ValidationDefinitions and Checkpoints, runs validation against tabular batches, and parses the JSON result for CI gating. Use when the user works with Great Expectations on Pandas, SQL, or Spark data.

Use the `@testbook` decorator to write conventional pytest unit tests against functions defined in Jupyter notebooks, without copy-pasting the function into a `.py` file. Covers `tb.ref()` (notebook object access) and `tb.inject()` (insert code into the kernel) for hermetic per-test setup. Use when unit-testing functions that live in a Jupyter notebook.

Validate Jupyter notebooks via the `pytest --nbval` plugin - re-execute cells and compare outputs to stored results. Cover the strict path (output match required), `--nbval-lax` (failure-only), `--sanitize-with` for dynamic outputs, and per-cell controls (`#NBVAL_SKIP`, `#NBVAL_IGNORE_OUTPUT`, `#NBVAL_RAISES_EXCEPTION`). Use when a repo ships `.ipynb` files as tutorials, docs, or analyses that must keep producing the same outputs after a dependency upgrade or source change.

Reference for Jepsen-style distributed-systems testing - consistency models hierarchy (linearizability vs sequential vs causal vs monotonic-reads vs eventual), nemesis primitives (network partitions, clock skew, kill nodes), workload generators, Knossos + Elle linearizability checkers. Reference-only because Jepsen tests are typically Clojure-bespoke per system; use this skill to evaluate vendor claims and structure your own test. Use when a datastore vendor advertises a consistency guarantee that has to be checked before adoption, when reading a published Jepsen report for gaps, or when a custom replicated store needs its own consistency test scoped.

Runs the Go race detector and goroutine-leak checker end-to-end: instrument with `go test -race`, read race reports, configure GORACE options, stress with `-count`/`-cpu`, detect goroutine leaks with go.uber.org/goleak, and gate both checks in CI. Use when a Go service has shared state accessed by concurrent goroutines, when a race-related incident needs a regression harness, or when adding `-race` to a CI matrix for a Go module. Does not cover barrier-based deterministic interleaving or forced goroutine scheduling; use race-condition-test-author for that.

Run Madge against a JS/TS production source tree to detect circular dependencies, find orphan modules, and visualize the module graph. Scoped to production code via `excludeRegExp` for test files. Use when a build compiles but throws `Cannot read property X of undefined` on a module that is clearly imported, or when a repo needs a CI gate that blocks new import cycles.

Run Lizard against production source to enforce per-function cyclomatic complexity (CCN), NLOC, and parameter-count thresholds - language-agnostic (30+ languages). Scoped to production code via `-x"./tests/*"`; test complexity is reviewed separately. Use when a codebase spans several languages and needs one complexity gate across all of them, or when a function has grown unreviewable and the team wants a numeric threshold in CI.

Validate Vega + Vega-Lite specifications against the JSON Schema (vega.github.io/schema), test cross-engine compatibility (Vega-Lite compiles to Vega per the canonical compiler), and verify data-binding correctness. Pair with d3-snapshot-tests when Vega specs render to SVG; pair with chartjs-snapshot-tests when rendered to Canvas. Use when application code generates Vega/Vega-Lite JSON specs at runtime (BI builders, spec templating) and those specs must be proven valid and correctly encoded before render, or before a Vega major-version upgrade.

Snapshot-test Chart.js charts - render via headless Chromium / jsdom + canvas mock, capture canvas pixels via `canvas.toDataURL()` + image-diff, disable animations (`options.animation = false`) for stable snapshots, test tooltip + legend interactions. Use when a project renders Chart.js charts and needs regression coverage of their rendered output.

Asserts Chrome extension message-passing behaviour against a running extension: one-shot `chrome.runtime.sendMessage` plus the literal `return true` that holds the response channel open for an async `sendResponse`, `chrome.tabs.sendMessage` into one tab's content script, long-lived `chrome.runtime.connect` ports and their `onDisconnect` triggers, web-page messages gated by `externally_connectable`, and `chrome.runtime.connectNative` native-messaging hosts. Covers the payload rules a test must respect (Chrome uses JSON serialization rather than structured clone, so `Map` / `Set` / `Date` do not round-trip; maximum message size is 64 MiB) and the first-listener-wins rule when several `onMessage` listeners are registered. Scope is messaging behaviour on an already-running extension, not the install or reload step. Use when a message reaches no listener, a `sendResponse` callback never fires, a port disconnects mid-test, or a page origin has to be proven allowed before publishing.

Authors and runs IBM Equal Access accessibility-checker scans - IBM's open-source a11y engine with WCAG 2.0 / 2.1 / 2.2 + US Section 508 rule sets, integrating with Node / Selenium / Puppeteer / Playwright / Karma / Cypress test runners. Distinguished by IBM's enterprise-tier rule coverage and Section 508 specificity. Use when the project ships to US federal / public-sector customers (Section 508 mandate) or when the team values IBM-branded a11y reporting.

Authors browser automation scripts using Puppeteer - Chrome / Chromium-only headless / headed automation, Page object via `page.*` API, network interception, PDF generation, screenshot capture, scraping. Distinct from Playwright (Puppeteer's older sibling, Chrome-only) - use Puppeteer for Chrome-only browser automation tasks (scraping, generating PDFs from HTML, screenshot pipelines) where Playwright's multi-browser support is unneeded overhead. Use when a project already depends on `puppeteer` / `puppeteer-core`, or when a Chrome-only script must emit PDFs, screenshots, or scraped data rather than assert on a page.

Move existing Codex chats/threads into saved Codex Projects by resolving chat titles and project names, generating a safe move plan, and launching a terminal helper that quits Codex, patches local Codex state after exit, then reopens Codex. Use when the user asks to organize Codex chats by Project, move chats into Projects, re-parent projectless Codex threads, or fix chats appearing outside the intended Project.

Fetch web content in multiple formats using fetch MCP tools. Use when WebFetch fails with 403/access errors, when fetching HTML pages, JSON APIs, plain text, readable article content, or YouTube transcripts. Triggers on mentions of fetching URLs, web scraping, reading web pages, downloading content, or accessing online resources.