# Skill Creator > Guide for creating and editing Claude Code skills. Use when user wants to create a new skill, update an existing skill, or needs help structuring a SKILL.md file. Use when this capability is needed. - Skill: `tomevault-io/skill-creator-151` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/skill-creator-151` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/skill-creator-151/raw - Safety review: pending (external: skill-scanner PASS, skillspector CAUTION) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/skill-creator-151 --- # Skill Creator ## Process ### 1. Gather requirements Ask the user: - What task/domain does the skill cover? - What specific use cases should it handle? - Does it need executable scripts or just instructions? - Any reference materials to include? If the user's description is already clear, skip straight to drafting. ### 2. Determine placement Infer from context, ask only if ambiguous: - **Global** (`~/.claude/skills/`) - across all projects - **Project** (`/.claude/skills/`) - repo-specific - **Plugin** (`/plugins//skills/`) - distributed via marketplace ### 3. Assess complexity **Simple** (just write the SKILL.md): - Purely instructional (workflow, guidelines, domain knowledge) - No supporting files needed **Full** (skill with bundled resources): - Needs scripts for deterministic/repeated operations - Needs reference docs (schemas, API docs, large knowledge bases) - Needs assets (templates, images, fonts) ### 4. Draft the skill **Simple path:** Create the directory and write SKILL.md directly. **Full path:** 1. Plan supporting files (what scripts/references/assets are needed) 2. Create the skill directory and subdirs 3. Write supporting files first (may need user input for assets/docs) 4. Write SKILL.md last, referencing the supporting files ### 5. Review with user Present draft and iterate. Skills improve most after real usage. ## Skill Structure ``` skill-name/ ├── SKILL.md # Main instructions (required) ├── references/ # Docs loaded into context on demand (optional) │ ├── api-reference.md │ └── schema.md ├── scripts/ # Deterministic code (optional) │ └── helper.py └── assets/ # Files used in output (optional) └── template.html ``` Reference supporting files from SKILL.md so Claude knows they exist: ```md - For API details, see [references/api-reference.md](references/api-reference.md) - For schema docs, see [references/schema.md](references/schema.md) ``` ## SKILL.md Format ```md --- name: skill-name description: Brief description of capability. Use when [specific triggers]. --- # Skill Name [Core instructions, workflows, and guidance] ``` ### Key frontmatter fields | Field | Description | | :------------------------- | :----------------------------------------------------------------------------------------------------------------------- | | `name` | Skill identifier, becomes `/slash-command`. Lowercase, hyphens, max 64 chars. | | `description` | What it does + when to trigger. Claude uses this to decide when to load the skill. | | `disable-model-invocation` | `true` to prevent Claude auto-loading (manual `/invoke` only). Use for side-effect workflows like deploy, commit. | | `user-invocable` | `false` to hide from `/` menu. Use for background knowledge Claude should load automatically but users shouldn't invoke. | | `allowed-tools` | Tools Claude can use without permission prompts when skill is active. E.g. `Read, Grep, Glob`. | | `context` | `fork` to run in an isolated subagent. Skill content becomes the subagent's task. | | `agent` | Subagent type when `context: fork`. Options: `Explore`, `Plan`, `general-purpose`, or custom agent name. | | `argument-hint` | Autocomplete hint, e.g. `[issue-number]` or `[filename]`. | ### String substitutions Use in skill content for dynamic values: - `$ARGUMENTS` - all arguments passed when invoking (`/skill-name arg1 arg2`) - `$0`, `$1`, `$2` - individual arguments by position - `${CLAUDE_SESSION_ID}` - current session ID - `` !`command` `` - preprocesses shell command output into the prompt before Claude sees it ## Writing Guidelines **Description** is the most important field. It's the only thing Claude sees when deciding which skill to load. Include: - First sentence: what the skill does - Second sentence: when to trigger it (keywords, file types, scenarios) - Max 1024 chars, third person **Two types of skill content:** - **Reference** - knowledge Claude applies to current work (conventions, patterns, domain knowledge). Runs inline alongside conversation. - **Task** - step-by-step instructions for a specific action (deploy, commit, code generation). Often paired with `disable-model-invocation: true`. **Body** should contain: - Procedural knowledge non-obvious to Claude - Concrete workflows with actionable steps - References to supporting files so Claude knows they exist **Keep SKILL.md lean.** Aim for under 200 lines, hard max 500. Move detailed material to supporting files. ## When to Add Scripts Add `scripts/` when: - Same code would be generated repeatedly - Operation needs deterministic reliability - Errors need explicit handling Scripts save tokens and improve reliability vs regenerating code each time. **Path resolution:** For plugin skills, reference scripts with `${CLAUDE_SKILL_DIR}/scripts/helper.js` (relative paths won't resolve). Use `${CLAUDE_PLUGIN_ROOT}` only when referencing files outside the skill's own directory. For global/project skills, relative paths work fine. ## When to Split Files Split content out of SKILL.md when: - SKILL.md would exceed ~200 lines - Content covers distinct domains (separate files per domain) - Advanced features are rarely needed - Large schemas, API docs, or knowledge bases Prefer multiple focused files over one large reference file. E.g. `api-reference.md`, `schema.md`, `examples.md` rather than a single `reference.md` with everything. For large files (>10k words), include grep patterns in SKILL.md so Claude can search efficiently. ## Review Checklist After drafting, verify: - [ ] Description includes triggers ("Use when...") - [ ] SKILL.md is lean (under ~200 lines) - [ ] No time-sensitive information - [ ] Concrete examples included where helpful - [ ] All supporting files referenced in SKILL.md - [ ] No duplicate info between SKILL.md and supporting files --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/lttr) — claim your Tome and manage your conversions.