Apply when creating or editing prompts targeting Claude Fable 5 (model ID claude-fable-5). Covers effort-level selection, longer autonomous turns, brief-instruction steering, progress-claim grounding, action boundaries, parallel subagent orchestration, memory systems, early-stopping and context-budget mitigations, send-to-user tooling, reasoning-extraction refusal avoidance, and migration from Opus 4.8.
Apply when creating or editing prompts targeting Claude Opus 5 (model ID claude-opus-5). Covers response and deliverable length, progress narration, over-verification removal, subagent damping, self-correction narration, scope constraints, effort-level implications, code review harnesses, XML structure, long-context patterns, and migration from Opus 4.8. Do not apply to other Claude models — for Fable 5 use fable-5-prompting.
Ultra-compressed communication mode for conversation output. Three levels: lite (matches default style), full (fragment-heavy, drop articles), ultra (abbreviations, arrows). Default on /caveman is full. Activates when user says "caveman mode", "talk like caveman", "use caveman", or invokes /caveman. Switch with /caveman lite|full|ultra.
Apply when creating, updating, or rewriting tasks in ClickUp. Covers ClickUp-specific field discipline (due dates, priority, assignees, tags, dependencies, linked tasks, subtasks, custom fields), MCP tool discovery, space introspection, and asking-over-defaulting. Pairs with ticket-writing for body content. Project conventions always override these defaults.
Apply when writing or editing C# (.cs) files. Behavioral corrections for error handling, resource management, async patterns, data modeling, type safety, nullability, security defaults, and common antipatterns. Project conventions always override these defaults.
Apply when writing or editing Dart (.dart) files. Behavioral corrections for null safety, async patterns, type system, error handling, and common antipatterns. Project conventions always override these defaults.
Apply when implementing Domain-Driven Design patterns in Python (.py) files. Covers tactical patterns (entities, value objects, aggregates, domain events, repositories), layered architecture with dependency inversion, persistence strategies, validation boundaries, and common DDD anti-patterns. Best suited for projects with complex business rules spanning multiple entities. For top-level project layout by business capability see feature-driven-architecture-python; this skill governs the internals of slices with complex invariants.
Apply when structuring or restructuring a Python backend by business capability (vertical slices) — laying out a new project, reorganizing a layered codebase, or drawing feature boundaries. Governs top-level layout; for the internals of a complex slice see ddd-architecture-python. Covers directory layout, feature boundaries, inter-feature communication, database model ownership, migration strategies, boundary enforcement, testing across features, and migration from layered architectures. FastAPI-focused; the layout patterns port to Flask. Best suited for projects with 5+ distinct features.