Respond in the voice of a salty seafaring pirate — swapping everyday words for nautical slang, droppin' the 'g' on -ing endings, and sprinkling in sea metaphors, while keeping all code, commands, and technical facts exact. Use when the user asks Claude to talk like a pirate, go full buccaneer, or invokes /pirate-speak. Applies the persona to all replies until the user asks to stop.

Write and run HTTP API tests in Hurl's plain-text format. Use when testing REST/GraphQL APIs, writing integration or smoke tests for HTTP endpoints, chaining requests with captured values, polling async APIs, converting curl commands into maintainable tests, or producing executable API documentation. Trigger on .hurl files, the hurl or hurlfmt CLI, jsonpath/xpath response assertions, or any ask to 'test an API' with a simple text-based tool.

AST-based code search, lint, and rewrite using ast-grep. Use when finding code patterns structurally (not textually), writing lint rules, building codemods, or migrating API usage across a codebase. Prefer over regex grep when the match target is a syntactic construct (function call, import, class field, assignment).

Answer questions about the Zod schema validation library and help build schemas, parsers, refinements, transforms, codecs, and error formatters. Use when developers: (1) ask about Zod APIs like `z.object`, `z.string`, `z.array`, `z.union`, `z.discriminatedUnion`, `parse`, `safeParse`, `z.infer`; (2) define request/response/form schemas in TypeScript; (3) handle `ZodError` or customize error messages; (4) migrate between Zod v3 and v4 (entry-point split, `formatError` → `treeifyError`/`prettifyError`, unified `error` param replacing `message`/`errorMap`). Triggers on: "zod", "z.object", "z.string", "z.array", "z.union", "z.infer", "z.input", "z.output", "ZodError", "$ZodError", "safeParse", "parseAsync", "z.codec", "treeifyError", "prettifyError", "flattenError", "discriminatedUnion", "zod/v4", "zod/v3", "zod/mini", "z.coerce", "superRefine".

Answer questions about better-auth and help build authentication features. Use when developers: (1) ask about better-auth APIs like `betterAuth`, `auth.api.*`, `authClient.*`; (2) wire up sign-in / sign-up / sessions; (3) integrate framework adapters (Next.js, Nuxt, SvelteKit, Hono, Astro, Bun, Express); (4) add plugins (organization, two-factor, magic-link, passkey, oauth-proxy); (5) configure DB adapters (Prisma, Drizzle, Kysely, Mongoose). Triggers on: "better-auth", "betterAuth", "authClient", "sign in flow", "auth session", "social login", "magic link", "passkey", "organization plugin".

Use when creating or editing Nullstone IaC YAML files under `.nullstone/` — adding or wiring apps, datastores, networks, domains, subdomains, ingresses, clusters, cluster-namespaces; setting `vars`, `environment`, `connections`, or `capabilities`; configuring `events`. Triggers on file paths `.nullstone/config.yml`, `.nullstone/{env}.yml`, `.nullstone/previews.yml`, and anything under `.nullstone/stacks/{stack}/`.

Install, uninstall, or list tessl skill tiles for installed mks plugins. Use this when asked to "install the tile for an mks plugin", "uninstall the tile for an mks plugin", "list tiles for an mks plugin", "tessl install PLUGIN", "tessl uninstall PLUGIN", or "tessl list". This skill is only for the mks CLI — not for any other plugin system.

Manage the mks CLI and its plugins. Use this when installing, listing, updating, or removing skills plugins (e.g., "install cherry-pick-filter plugin", "list installed plugins", "update plugins").

Sync a working branch to a clean merge branch by cherry-picking commits that don't touch filtered paths. Use this script only when syncing branches to beta/main during PR preparation or updates (e.g., "sync to beta", "cherry-pick to beta", "update PR branch").

Expert guidance for configuring and deploying the OpenTelemetry Collector. Use when setting up a Collector pipeline, configuring receivers, exporters, or processors, deploying a Collector to Kubernetes or Docker, or forwarding telemetry to Dash0. Triggers on requests involving collector, pipeline, OTLP receiver, exporter, or Dash0 collector setup.

Configures trace spans, defines custom metrics, sets up log exporters, and optimizes sampling strategies for OpenTelemetry instrumentation. Use when instrumenting applications with traces, metrics, or logs. Triggers on requests for observability, telemetry, tracing, metrics collection, logging integration, or OTel setup.

OpenTelemetry Transformation Language (OTTL) expert. Use when writing or debugging OTTL expressions for any OpenTelemetry Collector component that supports OTTL (processors, connectors, receivers, exporters). Triggers on tasks involving telemetry transformation, filtering, attribute manipulation, data redaction, sampling policies, routing, or Collector configuration. Covers syntax, contexts, functions, error handling, and performance.

Use this skill when the user asks to retrieve online book metadata, list editions, identify authors and publishers, find publication details, surface subjects, display cover image URLs, or cite Open Library source URLs by ISBN, title, author, or broad book query. This skill uses Open Library for read-only public book metadata. Do not use this skill for ebook downloads, shopping links, review aggregation, broad reading recommendations, metadata editing, or claims about any user's personal collection.