context-witness
Decide between Context Tag witness and capability patterns for dependency injection, understanding coupling trade-offs
domain-modeling
Create production-ready Effect domain models using Schema.TaggedStruct for ADTs, Schema.Data for automatic equality, with comprehensive predicates, orders, guards, and match functions. Use when modeling domain entities, value objects, or any discriminated union types.
domain-predicates
Generate comprehensive predicates and orders for domain types using typeclass patterns
effect-ai-language-model
Master the Effect AI LanguageModel service for text generation, structured output, streaming, and tool calling. Use when working with LLM interactions, schema-validated responses, or building conversational AI systems.
atom-state
Implement reactive state management with Effect Atom for React applications
codebase-explorer
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the-vm-standard
The VM Standard - inviolable covenants governing View Model architecture in this codebase. These covenants SHALL NOT be violated under any circumstance.
command-executor
Execute system commands and manage processes using Effect's Command module from @effect/platform. Use this skill when spawning child processes, running shell commands, capturing command output, or managing long-running processes with cleanup.
ai-context-writer
Create and update ai-context.md files that document modules for AI assistants. Use when adding documentation for packages, apps, or external references that should be discoverable via /modules commands.
architecture-analysis
Architectural dependency analysis and impact assessment. Use for: (1) Blast radius - who depends on a service, what breaks if I change it; (2) Dependency tree - what does a service depend on (ancestors/upstream); (3) Root cause analysis - find shared dependencies when multiple services fail; (4) Architecture metrics - coupling (density), depth (diameter), connectivity; (5) Domain discovery - identify module boundaries via cut vertices; (6) Hot services - critical infrastructure with many dependents; (7) Impact assessment before changes; (8) Debugging cascading failures; (9) Identifying god services, tight coupling, deep hierarchies. Provides graph-based analysis via CLI commands: analyze, blast-radius, ancestors, common-ancestors, metrics, domains, hot-services. All agents can use this for architectural questions.
effect-ai-prompt
Build prompts for Effect AI using messages, parts, and composition operators. Covers the complete Prompt API for constructing, merging, and manipulating conversations with language models.
effect-ai-provider
Configure and compose AI provider layers using @effect/ai packages. Covers Anthropic, OpenAI, OpenRouter, Google, and Amazon Bedrock providers with config management, model abstraction, and runtime overrides for language model integration.
effect-ai-streaming
Master Effect AI streaming response patterns including start/delta/end protocol, accumulation strategies, resource-safe consumption, and history management with SubscriptionRef.
effect-ai-tool
Define and implement AI tools using @effect/ai's Tool and Toolkit APIs. Use when building LLM integrations with type-safe tool definitions, parameter validation, and handler implementations. Covers user-defined tools, provider-defined tools, and toolkit composition.
effect-concurrency-testing
Test Effect concurrency primitives including PubSub, Deferred, Latch, Fiber coordination, SubscriptionRef, and Stream. Use this skill when testing concurrent effects, event-driven systems, or fiber coordination.
effect-testing
Write comprehensive tests using @effect/vitest for Effect code and vitest for pure functions. Use this skill when implementing tests for Effect-based applications, including services, layers, time-dependent effects, error handling, and property-based testing.
error-handling
Implement typed error handling in Effect using Data.TaggedError, catchTag/catchTags, and recovery patterns. Use this skill when working with Effect error channels, handling expected failures, or designing error recovery strategies.
layer-design
Design and compose Effect layers for clean dependency management
parallel-explore
Parallel exploration of codebase questions by decomposing into independent tracks. Use when exploring architecture, understanding systems, or investigating complex questions that benefit from multiple perspectives.
pattern-matching
Master Effect pattern matching using Data.TaggedEnum, $match, $is, Match.typeTags, and Effect.match. Avoid manual _tag checks and Effect.either patterns. Use this skill when working with discriminated unions, ADTs, or conditional logic based on tagged types.
platform-abstraction
Use @effect/platform abstractions for cross-platform file I/O, process spawning, HTTP clients, and terminal operations. Apply this skill when writing code that interacts with the filesystem, spawns processes, makes HTTP requests, or performs console I/O to ensure portability across Node.js, Bun, and browser environments.
react-composition
Build composable React components using Effect Atom for state management. Use this skill when implementing React UIs that avoid boolean props, embrace component composition, and integrate with Effect's reactive state system.
react-vm
Implement the VM pattern using Effect and Effect-Atom for reactive, testable frontend state management. Use this skill when building React applications with View Models that bridge domain services and UI.
schema-composition
Master Effect Schema composition patterns including Schema.compose vs Schema.pipe, transformations, filters, and validation. Use this skill when working with complex schema compositions, multi-step transformations, or when you need to validate and transform data through multiple stages.
service-implementation
Implement Effect services as fine-grained capabilities avoiding monolithic designs
spec-driven-development
Implement the complete spec-driven development workflow from instructions through requirements, design, and implementation planning. Use this skill when starting new features or major refactorings that benefit from structured planning before coding.
typeclass-design
Implement typeclasses with curried signatures and dual APIs for both data-first and data-last usage
wide-events
Conceptual guide to wide events (canonical log lines) for observability. Use when thinking about instrumentation strategy, span annotations, or designing what context to capture.
writing-laws
Write formal laws and covenants for codebases using proper legal-style structure. Use when establishing inviolable standards, architectural constraints, or domain-specific rules that must be followed without exception.