/writing-skills

name: writing-skills
description: Creates and improves Claude Code skills following the official Anthropic spec and house standards. Use when creating new skills, modifying existing skills, or improving skill quality. Use when user says "create a skill", "write a skill", "add capability". Use when a repeated pattern should become reusable.

Writing Skills

Overview

**Writing skills IS structured documentation creation for process guidance.**

Analyze requirements clearly, design skill structure thoughtfully, implement with precision, validate functionality, and iterate based on feedback.

**Core principle:** Clear requirements and structured design lead to effective skills that truly guide agent behavior.

Task Initialization (MANDATORY)

Follow [task initialization protocol](../../references/task-initialization.md).

**Tasks:** 0. Fetch latest official skill spec 1. Analyze requirements 2. Design skill structure 3. Implement SKILL.md 4. Add references (if needed) 5. Validate structure 6. REFACTOR - quality review 7. Test with real usage

Announce: "Created 8 tasks (0–7). Starting execution..."

Skill Creation Process

| Phase | Focus | What You Do | |-------|-------|-------------| | **Requirements** | Understanding | Analyze what capability is needed and why | | **Design** | Structure | Plan skill organization, triggers, and content | | **Implementation** | Creation | Write skill following design and best practices | | **Validation** | Testing | Verify skill works correctly in real scenarios | | **Improvement** | Refinement | Iterate based on feedback and usage patterns |

Task 0: Fetch Latest Official Spec

**Goal:** Pull the current Anthropic skill spec before designing — never trust cached memory.

**Action:**

Skill tool: fetching-claude-docs
  component: skill
  question: "frontmatter fields (name, description), description trigger
             format, SKILL.md structure, references/ progressive disclosure,
             skill activation"

**Verification:** Received YAML with `source: https://code.claude.com/docs/en/skills.md` and non-empty `spec_excerpt`. Use as authoritative reference; if any rule in this SKILL conflicts with the fetched spec, the fetched spec wins.

Task 1: Analyze Requirements

**Goal:** Understand what skill to create and why. Present full analysis to user for confirmation.

Analyze and answer ALL questions below:

• What capability does this skill teach?
• What triggers should activate it? (specific phrases, symptoms)
• Is this reusable across projects, or project-specific?
• Does a similar skill already exist?
• What are the key design decisions? List alternatives considered and chosen approach with rationale.

**External search (optional):** If `claude-skills-mcp` available, search for existing community skills to adapt.

**MANDATORY: Present analysis to user.** Display ALL answers above in full detail, then ask user to confirm before proceeding. Do NOT summarize into a single sentence. Do NOT skip to next task without explicit user approval.

**Verification:** User has reviewed the full analysis and confirmed the direction.

Task 2: Design Skill Structure

**Goal:** Plan the skill's organization, triggers, and content.

**Before drafting, walk through [prompt-design-principles.md](../../references/prompt-design-principles.md):**

• 5-skeleton framework — every skill needs Role, Scope, Workflow, Standards, Completion. Confirm each has concrete content planned.
• Failure-mode reverse engineering — the Red Flags section should reflect specific failures you've observed or can predict, not generic warnings.
• Conditional dispatch — list task variants the skill handles and per-variant behavior before writing absolute rules.
• Creative-constraint balance — explicitly decide what can vary (form, solution options) vs. what must be fixed (process, verification, tool order).
• Completion semantics — the final task must have a binary pass/fail check, not a narrative "done" signal.

**Design considerations:** 1. What specific capability does this skill provide? 2. When should the skill be triggered? (specific phrases, symptoms) 3. What are the key tasks and workflow steps? 4. What supporting materials are needed? (references, examples)

**Structure planning:**

• Clear trigger conditions in description
• Logical task sequence
• Verification criteria for each task
• Red flags and common mistakes

**Verification:** Have clear design plan with triggers, tasks, and structure defined.

Task 3: Implement SKILL.md

**Goal:** Create the skill following the design plan and best practices.

Skill Structure

skill-name/
├── SKILL.md           # Required (<300 lines)
├── scripts/           # Optional: executable tools
└── references/        # Optional: detailed docs

**If the skill includes scripts:** Use project's primary language if detectable (check `package.json`, `go.mod`, `Cargo.toml`, `pyproject.toml`, etc.); default to Python when unclear. Read [cross-platform-scripts.md](../../references/cross-platform-scripts.md) for mandatory cross-platform rules (paths, shell commands, line endings).

Naming Convention

**Gerund form** (verb + -ing): `writing-skills`, `processing-pdfs`

• Lowercase, hyphens, numbers only
• Max 64 characters
• Avoid: `helper`, `utils`, `anthropic`, `claude`

SKILL.md Format

See [references/spec.md](references/spec.md) for full frontmatter specification (fields, arguments, model selection, context:fork).

Context and Agent Selection

| Use Case | context | agent | Rationale | |----------|---------|-------|-----------| | Inline knowledge (conventions, patterns) | (none) | (none) | Runs in main conversation, Claude applies alongside current context | | Analysis or exploration task | `fork` | `Explore` | Isolated context, read-only tools, prevents context pollution | | Planning task | `fork` | `Plan` | Isolated context, research-focused | | Task with side effects (deploy, commit) | `fork` | (non