Create Skill from Custom Approach

Guide to save a successful custom security testing approach as a reusable skill, including steps for parameter definition, pattern extraction, and file creation.

Sby Skills Guide Bot
SecurityIntermediate
007/23/2026
Claude Code
#skill-creation#reusable#security-testing#custom-approach#token-budget

Recommended for


description: Save a custom approach as a reusable skill dispatch: skill

/create-skill - Save Custom Approach as Reusable Skill

Save a successful custom approach as a reusable specialist skill.

When to Use

After you've helped the user with a custom security testing approach:

  • Custom analysis focus (e.g., "focus on API security only")
  • Custom priority order (e.g., "check auth before secrets")
  • Custom techniques (e.g., "specific testing methodology")
  • Successful findings (approach actually worked)

What This Does

Guides skill creation process:

Step 1: Capture Successful Approach

What was successful about this approach?

Examples:
- Custom priorities: Auth → API security → Business logic
- Specific focus: API endpoint authentication testing
- Custom technique: Token generation + endpoint fuzzing
- Domain expertise: Mobile app security patterns

Step 2: Define Skill Parameters

Skill name: [descriptive_name]
Trigger keywords: [when should this auto-load?]
Domain: [what type of targets?]

Examples:
- Name: api_security_auth_focus
- Keywords: API, REST, authentication, admin panel
- Domain: Web APIs with authentication

Step 3: Extract Reusable Patterns

Review approach for:

  • ✓ Generalizable patterns (not hardcoded to one target)
  • ✓ Reusable priorities (applicable to similar targets)
  • ✓ Tool combinations (what worked together)
  • ✗ Target-specific details (remove these)

Step 4: Validate Token Budget

Skill size: ___ tokens (must be <500 tokens)
Current total skills: ___ (warn if >10 skills)
Session impact: +___ tokens when auto-loaded

Step 5: Create Skill File

Save to: .claude/skills/[skill_name]/SKILL.md (the canonical Claude Code skills directory). For single-file skills, .claude/skills/[skill_name].md also works — Claude Code's skill discovery walks .claude/skills/ and picks up both layouts.

(Pre-fix this said tiers/specialists/custom/[name].md. That path is from an earlier RAPTOR layout that predates Claude Code's skills mechanism — files there aren't auto-loaded by Claude Code today, so saving new skills there would have made them invisible to the LLM. Existing files under tiers/personas/ and tiers/specialists/ are still loaded VIA EXPLICIT prompts, but new skills should go under .claude/skills/ for auto-load.)

Skill structure:

# [Skill Name]
# Created: [date]
# Source: Successful approach from [session]
# Token cost: [X] tokens
# Auto-loads: [trigger keywords]

## Core Philosophy
[What makes this approach unique/successful]

## When to Use
[What types of targets/situations]

## Approach
[Successful priorities, techniques, tools]

## Integration with Python
[How this guides Python execution parameters]

Step 6: Test Auto-Loading

Verify skill will auto-load correctly:

  • Keywords defined clearly
  • File in correct location
  • Token budget acceptable

Token Budget Guidelines

Skill size limits:

  • Minimum: 200 tokens (enough for useful content)
  • Recommended: 300-400 tokens (sweet spot)
  • Maximum: 500 tokens (hard limit, enforced)

Total skills warning:

  • Yellow (5 skills): 1,500-2,000 tokens in skills
  • Red (10 skills): 3,000-4,000 tokens (approaching budget)
  • Critical (15+ skills): Consider consolidating or removing unused

Example Skill Creation

User: /create-skill

Claude: What successful approach should we save?

User: "We focused on API authentication, checking auth bypass before anything else, and it found critical issues faster"

Claude:
  ✓ Extracting approach patterns...

  Skill preview:
  - Name: api_auth_priority
  - Keywords: API, REST, authentication, auth bypass
  - Focus: Authentication issues in web APIs
  - Priority: Auth bypass → API security → Input validation
  - Size: 380 tokens ✓

  Create this skill? [Y/n/Customize]

User: Y

Claude: ✓ Created: .claude/skills/api_auth_priority/SKILL.md
        Will auto-load when keywords match: API, authentication

        Test it now? Run /scan on API codebase

Quality Checks

Before saving skill:

  • [ ] Not overfitted to one target (generalized patterns)
  • [ ] Token limit respected (<500 tokens)
  • [ ] Keywords defined (will auto-load correctly)
  • [ ] Approach documented (clear priorities/techniques)
  • [ ] Integration clear (how it guides Python parameters)

Maintenance

Skills are stored in: .claude/skills/

Manage skills:

  • List: ls .claude/skills/
  • Disable: Add .disabled suffix to the skill directory or file
  • Remove: Delete the skill directory (or the bare .md file)
  • Edit: Modify the skill's SKILL.md (or single-file .md) directly

(Pre-fix this section pointed at tiers/specialists/custom/ — an earlier RAPTOR layout that predates Claude Code's skills mechanism. Files there aren't auto-loaded today, so saving new skills there made them invisible to the LLM.)

Quarterly review prompt (if 5+ skills exist):

Review custom skills? Usage stats available.
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