Claude Skills

Enforce testing best practices - AAA pattern, naming conventions, isolation, coverage thresholds. Blocks non-compliant tests. Use when writing or reviewing tests.

End-to-end type safety with Zod, tRPC, Prisma, and TypeScript 5.7+ patterns. Use when creating Zod schemas, setting up tRPC, validating input, implementing exhaustive switch statements, branded types, or type checking with ty.

Unit testing patterns and best practices. Use when writing isolated unit tests, implementing AAA pattern, designing test isolation, or setting coverage targets for business logic.

VCR.py HTTP recording for Python tests. Use when testing Python code making HTTP requests, recording API responses for replay, or creating deterministic tests for external services.

Comprehensive feature verification with parallel analysis agents. Use when verifying implementations, testing changes, validating features, or checking correctness.

Manage multiple Claude Code instances across git worktrees. Check status, claim/release file locks, sync decisions, and prevent conflicts. Use when coordinating multiple worktrees or Claude instances.

Safe database schema changes without downtime using expand-contract pattern and online schema changes. Use when deploying schema changes to production without service interruption.

Local LLM inference with Ollama. Use when setting up local models for development, CI pipelines, or cost reduction. Covers model selection, LangChain integration, and performance tuning.

Saga patterns for distributed transactions with orchestration and choreography approaches. Use when implementing multi-service transactions, handling partial failures, or building systems requiring eventual consistency with compensation.

Vercel agent-browser CLI for headless browser automation. 93% less context than Playwright MCP. Snapshot + refs workflow with @e1 @e2 element references. Use when automating browser tasks, web scraping, form automation, or content capture.

Statistical and quality drift detection for LLM applications. Use when monitoring model quality degradation, input distribution shifts, or output pattern changes over time.

Strawberry GraphQL library for Python with FastAPI integration, type-safe resolvers, DataLoader patterns, and subscriptions. Use when building GraphQL APIs with Python, implementing real-time features, or creating federated schemas.

CQRS (Command Query Responsibility Segregation) patterns for separating read and write models. Use when optimizing read-heavy systems, implementing event sourcing, or building systems with different read/write scaling requirements.

Text embeddings for semantic search and similarity. Use when converting text to vectors, choosing embedding models, implementing chunking strategies, or building document similarity features.

RFC 9457 Problem Details for standardized HTTP API error responses. Use when implementing problem details format, structured API errors, error registries, or migrating from RFC 7807.

Use when completing tasks, code reviews, or deployments to verify work with evidence. Collects test results, build outputs, coverage metrics, and exit codes to prove work is complete.

LLM fine-tuning with LoRA, QLoRA, DPO alignment, and synthetic data generation. Efficient training, preference learning, data creation. Use when customizing models for specific domains.

React Hook Form v7 with Zod validation, React 19 useActionState, Server Actions, field arrays, and async validation. Use when building complex forms, validation flows, or server action forms.

Quick recovery from common git mistakes including undo commits, recover branches, and reflog operations. Use when you need to undo, recover, or fix Git history.

Reranking patterns for improving search precision. Use when implementing cross-encoder reranking, LLM-based relevance scoring, or improving retrieval quality in RAG pipelines.

Value Proposition Canvas, Jobs-to-be-Done (JTBD), Build/Buy/Partner decisions, and strategic product frameworks. Use when validating value propositions, understanding customer needs, or making strategic technology decisions.

Use this skill for internationalization (i18n) in React applications. Covers ALL user-facing strings, date/time handling, locale-aware formatting (useFormatting hook), ICU MessageFormat, Trans component, and RTL/LTR support.

API rate limiting with token bucket, sliding window, and Redis distributed patterns. Use when implementing rate limits, throttling requests, handling 429 Too Many Requests, protecting against API abuse, or configuring SlowAPI with Redis.

Advanced RAG with Self-RAG, Corrective-RAG, and knowledge graphs. Use when building agentic RAG pipelines, adaptive retrieval, or query rewriting.