feature-file
Manage features.yml for tracking requirements and progress; use proactively ONLY when features.yml already exists, or invoke manually to create one; complements TodoWrite for persistent project state.
waterfall-development
Enforces strict waterfall development workflow with phase gates. Use when (1) features.yml exists in project root, (2) user asks to implement/develop/build a feature, (3) user explicitly requests waterfall workflow. Creates features.yml if missing when invoked.
commit-message
Format git commit messages combining Conventional Commits summary lines with Linux kernel-style bodies. Use when writing, reviewing, or formatting commit messages.
deep-research
Conduct rigorous, multi-source deep research with workflowz orchestration, iterative retrieval, claim-level evidence tracking, source verification, adversarial review, and cited synthesis. Use for complex questions requiring broad coverage, multiple independent sources, comparison, contradiction handling, or an auditable research report; do not use for a quick factual lookup.
git-commit
Guide for breaking changes into logical, atomic commits using interactive staging. Use when committing changes that span multiple concerns, when needing to stage parts of files (hunks), when asked to create well-organized commit history, or when changes should be split into multiple commits.
software-architecture
Document software architecture using ARCHITECTURE.md and docs/*.md files with Mermaid diagrams. Use proactively when ARCHITECTURE.md exists in project root, or invoke to create initial architecture documentation. Covers system design, data flows, component relationships, and code organization with references to key entry points and abstractions.
structured-logging
Guide for writing effective log messages using wide events / canonical log lines. Use when writing logging code, adding instrumentation, improving observability, or reviewing log statements. Teaches high-cardinality, high-dimensionality structured logging that enables debugging.
alloy-modeling
Model and analyze relational systems with Alloy. Use when: designing object graphs, authorization rules, topology constraints, schemas, ownership relations, or other structure-heavy systems; writing Alloy signatures, relations, facts, predicates, assertions, and scope-bounded checks; debugging counterexample instances; or deciding what should be abstracted into a bounded relational model.
formal-verification
OPT-IN workflow for involved formal-verification planning. Use only when: the user explicitly asks for formal verification, this skill is referenced by workspace instructions, or the task explicitly calls for structuring a full formal-verification effort across models, refinement steps, and implementation-level proof obligations.
tlaplus-modeling
Model and reason about concurrent or distributed systems with TLA+ and PlusCal. Use when: designing multithreaded or distributed behavior before code exists, deriving invariants from an informal design, writing TLA+ specs, creating PlusCal algorithms, model checking with TLC, organizing multi-module specifications, debugging verification failures, or reducing state space. Covers informal concurrency design, MCP tool usage, PlusCal preferred syntax (call/await over goto), TLA+ module organization, and state-space optimization.