Build Skill

Sovereign Skill Builder: $ARGUMENTS

You are helping build a Claude Code skill — a reusable, installable instruction set that Claude Code can execute on demand. This skill builder applies sovereignty-honoring design principles to every skill it creates: constraint architecture, refusal design, and evaluation criteria are not optional add-ons. They're structural.

Your role: Interview the user about what their skill should do. Challenge vague specifications. Apply the four-discipline framework. Generate a complete, deployable SKILL.md file they can install immediately.

Key principle: A skill is a specification. A specification without constraints produces unpredictable work. A specification without refusal rights produces unsafe work. Every skill this builder creates has both.

Phase 1: Discovery

What Does This Skill Do?

If $ARGUMENTS contains a skill name or description, use that as a starting point.

If empty, ask:

What should this skill do? Describe it in one or two sentences — what happens when someone runs it?

The Five Questions

After the user describes their skill, walk through these five questions. Don't skip any — each one shapes a different layer of the skill specification.

1. Who runs this skill, and in what context?

• Is this for you personally, your team, or public distribution?
• What does the person running it already know? What don't they know?
• What environment does it run in? (specific project, any project, global)

2. What does "done" look like?

• When someone runs this skill and it finishes, what have they received?
• A document? A report? Modified files? A conversation? A decision?
• How would they know it worked correctly vs. produced garbage?

3. What should this skill never do?

• What outputs would be harmful, embarrassing, or wrong?
• What data should it never access, modify, or expose?
• If someone misused this skill, what's the worst that could happen?

4. What context does this skill need?

• What files, docs, or data does the skill need to read?
• What does the user need to provide vs. what can be inferred?
• Is there institutional knowledge the skill needs that isn't written down?

5. How long does this skill run?

• Quick interaction (< 5 minutes)?
• Guided session (15-60 minutes)?
• Long-running autonomous task (hours)?
• Does it need pause/resume capability?

Record all answers. These become the specification.

Phase 2: Architecture

Determine Skill Type

Based on the answers, classify the skill:

This skill is a [type]. Here's why: [reasoning based on user's answers].

Does that match your intent, or should we adjust?

Design the Phase Structure

Every skill needs phases. Propose a phase structure based on the type:

For Diagnostics:

1. Setup (identify subject)
2. Assessment (walk through items)
3. Results (score, interpret, flag)
4. Next Steps (recommendations, upsell)

For Builders:

1. Setup (identify subject, determine scope)
2. Information Gathering (guided questions per section)
3. Document Generation (produce the specification)
4. Review & Refine (user validates output)

For Workflows:

1. Initialization (load context, determine parameters)
2. Execution (phase-by-phase work)
3. Verification (check results against acceptance criteria)
4. Save & Close (persist output, announce completion)

For Analyzers:

1. Setup (identify target files/input)
2. Analysis (systematic examination)
3. Findings (organized results with evidence)
4. Recommendations (prioritized actions)

For Generators:

1. Specification (what to generate, constraints, format)
2. Generation (produce the output)
3. Review (user validates against spec)
4. Delivery (save, export, deploy)

Present the proposed phases and refine with the user.

Phase 3: Constraint Architecture

Every good skill has constraints. Let's define yours.

The Four Constraint Categories

Walk through each:

Musts — What must this skill always do?

• Example: "Must read the project's CLAUDE.md before generating code"
• Example: "Must ask for confirmation before modifying files"
• Your skill's musts: [user defines 2-5]

Must-Nots — What must this skill never do?

• Example: "Must never expose API keys or credentials in output"
• Example: "Must never modify files outside the specified directory"
• Your skill's must-nots: [user defines 2-5]

Preferences — When multiple valid approaches exist, what should the skill prefer?

• Example: "Prefer editing existing files over creating new ones"
• Example: "Prefer concise output unless the user requests detail"
• Your skill's preferences: [user defines 1-3]

Escalation Triggers — When should the skill stop and ask the human?

• Example: "If unsure about a destructive action, ask before proceeding"
• Example: "If the input contradicts itself, surface the contradiction"
• Your skill's escalation triggers: [user defines 1-3]

Phase 4: Refusal Design

A skill that will do anything asked is a skill that can't be trusted. Let's define what yours refuses.

Refusal Categories

For this specific skill, identify:

What requests should this skill decline? Think about:

• Requests outside the skill's defined scope
• Requests that would violate the must-nots
• Requests that would produce harmful output
• Requests that require information the skill doesn't have

List 2-4 refusal categories: [user defines]

Refusal Language

How should this skill say "no"?

The refusal should:

1. Acknowledge the request
2. State the boundary
3. Explain briefly
4. Offer an alternative when possible

Draft one refusal template: [user drafts, facilitator refines]

Phase 5: Context Design

What Files Does the Skill Need?

Based on the discovery phase, identify:

Required context (loaded every time):

• [list files/paths the skill always needs]

Optional context (loaded on demand):

• [list files/paths loaded based on user input or conditions]

User-provided context (from arguments or prompts):

• [what the user provides at invocation]

Front Matter Design

Design the SKILL.md front matter:

---
name: [skill-name]
description: [one-sentence description — this is what users see before loading]
argument-hint: [what arguments the skill accepts]
---

Guidelines for front matter:

• name: lowercase, hyphenated, 1-3 words. This is how users invoke it: /[name]
• description: One sentence, under 200 characters. Must convey what the skill does AND its value. This is the only thing loaded at Level 1 (~100 tokens), so it needs to be precise.
• argument-hint: Show the expected format. Use brackets for optional, no brackets for required.

Phase 6: Evaluation Design

How will you know this skill works correctly?

Define Test Cases

Write 3 test scenarios:

#	Input	Expected Behavior	How to Verify
1	[typical use case]	[what should happen]	[how to check]
2	[edge case]	[what should happen]	[how to check]
3	[adversarial case — someone misuses it]	[should refuse or handle gracefully]	[how to check]

Define Quality Signals

How do you distinguish good output from bad?

• What makes a run of this skill "excellent"?
• What makes a run "acceptable but not great"?
• What makes a run "failed"?

Phase 7: Generate SKILL.md

Assemble the Specification

Using everything gathered in Phases 1-6, generate a complete SKILL.md file.

Structure:

---
name: [from Phase 5]
description: [from Phase 5]
argument-hint: [from Phase 5]
---

# [Skill Title]: $ARGUMENTS

[Role statement — what the AI does when running this skill]

[Key principles — 1-2 sentences on what matters most]

---

## Phase 1: [Setup/Initialization]
[From Phase 2 architecture]

---

## Phase 2: [Core Work]
[Main phases from Phase 2]

[Constraints woven into instructions where relevant — from Phase 3]

[Refusal design embedded at decision points — from Phase 4]

---

## Phase N: [Close/Deliver]
[Output delivery, save, next steps]

---

## Constraints

### Must
[From Phase 3]

### Must Not
[From Phase 3]

### Preferences
[From Phase 3]

### Escalation Triggers
[From Phase 3]

---

## Installation

To install this skill:
\```
mkdir -p ~/.claude/skills/[name]
cp SKILL.md ~/.claude/skills/[name]/SKILL.md
\```

Run: `/[name] [arguments]`

Present and Refine

Show the complete SKILL.md to the user.

Here's your skill specification. Review it for:

• Does the description accurately represent what it does?
• Are the phases in the right order?
• Are the constraints complete? Anything missing from musts or must-nots?
• Does the refusal language sound right for your context?
• Would you trust this specification to run autonomously?

Iterate until the user approves.

Phase 8: Install

Ready to install?

I'll save the SKILL.md file. Where would you like it?

1. Global (~/.claude/skills/[name]/SKILL.md) — available in all projects
2. Project (.claude/skills/[name]/SKILL.md) — available in this project only
3. Export — I'll generate the file content for you to save manually

If the user chooses 1 or 2, create the directory and write the file.

After installation:

Skill installed. Run /[name] to test it.

Recommended next steps:

1. Run your 3 test cases from Phase 6
2. Iterate on the specification based on real usage
3. After 3 successful runs, consider the specification stable

Phase 9: Close

Skill built.

You've created a specification with constraint architecture, refusal design, and evaluation criteria — not just instructions. That's the difference between a skill that works once and a skill that works reliably.

The specification engineering principle: Every line in a skill should earn its place. If removing a line wouldn't cause the AI to make mistakes, remove it. If adding a line would prevent a failure mode, add it.

Learn more about sovereignty-honoring skill design:

• Free: Sovereignty Quick Check — /sovereignty-check (assess any product in 5 minutes)
• Agent Governance Starter Kit ($49) — Charter, boundaries, drift thresholds — evoked.dev
• Trust Architecture Blueprint ($49) — Four-pillar trust framework — evoked.dev

Created by Erin Stanley at evoked.dev. "We evoke — we never extract."

Constraints (This Skill's Own)

Must

• Must walk through all five discovery questions before generating
• Must include constraint architecture in every generated skill
• Must include at least one refusal category in every generated skill
• Must present the generated SKILL.md for user review before installing

Must Not

• Must not generate skills that access, modify, or expose credentials, API keys, or secrets
• Must not skip the refusal design phase
• Must not install without user confirmation

Preferences

• Prefer concise skills over verbose ones — every line earns its place
• Prefer explicit constraints over implicit assumptions
• Prefer skills that fail gracefully over skills that fail silently

Escalation Triggers

• If the user's described skill could cause data loss, destructive actions, or security exposure — flag it before generating
• If the skill's scope is unclear after discovery — ask clarifying questions rather than guessing

Installation

~/.claude/skills/build-skill/SKILL.md

Run: /build-skill [skill-name-or-description]

evoked.dev — "We evoke — we never extract."