Functional Skill Creator
Create or migrate functional skills from requirements or legacy code.
Installation
- Make sure Claude is on your device and in your terminal.
Skills load from
~/.claude/skills/when Claude Code starts up — so you need it on your machine first. If you don't have it yet, install it once with the command below, then runclaudein any terminal to verify.One-time setupnpm i -g @anthropic-ai/claude-codeAlready have it? Skip ahead.
- Paste into Claude Code or into your terminal.
This copies the whole skill folder into
~/.claude/skills/fskill-creator-shopee-eng/— the SKILL.md plus any scripts, reference docs, or templates the skill ships with. Safe default: works for every skill.Faster alternative (instruction-only skills)
Skips the clone and grabs only the SKILL.md file. Don't use this if the skill ships Python scripts, reference markdowns, or asset templates — they won't be downloaded and the skill will fail when it tries to load them.
Quick install (SKILL.md only)Sign up to copy - Restart Claude Code.
Quit and reopen Claude Code (or any other agent that loads from
~/.claude/skills/). New skills are picked up on startup. - Just ask Claude.
Skills auto-activate when your request matches the skill's description — no slash command needed. Trigger phrases live in the skill's own frontmatter; you can read them in the “What this skill does” section above.
Prefer to read the source first? Open on GitHub.
When Claude uses it
Create, maintain, or migrate functional skills; supports creating from a requirement brief and migrating an existing legacy skill directory into a functional skill structure.
What this skill does
fskill-creator
Goal
Unify the create and migrate lanes to produce a self-contained, reviewable, testable functional agent skill directory. The main skill handles routing, blueprint normalization, shared artifact generation, runtime capability provisioning, file writing, and validation; sub-skills only handle pre-analysis for their respective input forms.
Use this skill when the user wants to "generate a functional skill", "create a functional skill", "add functions to an existing functional skill", or "migrate an existing legacy skill directory into a functional skill".
Principles
- The main
SKILL.mdonly orchestrates the shared create / migrate / enhance / validate workflow. - Create and migrate are two pre-lanes; they must first converge into a unified
skill_blueprint. - Function-specific behavior lives in
functions/*.md; create / migrate specific pre-behavior lives insub-skills/*/functions/*.md. - Shared vocabulary, policies, and schemas live in
references/*.md. - Deterministic parsing, formatting, validation, and mechanical transforms live in
scripts/. - Report, unit test, viewer, and testcase capabilities are maintained only once in the main skill, and vendored into the target skill by
add_runtime_capabilities. - Preserve user-provided domain constraints; the migrate lane must also preserve legacy behavior evidence.
- When the user has not approved direct modification, generated files should be treated as proposals.
Sub-Skills
| Sub-skill | When | Responsibility | Output |
|---|---|---|---|
sub-skills/create | User provides a new skill brief or wants to enhance an existing functional skill | Normalize requirements, target path, inputs/outputs, constraints, and viewer choices | create_context |
sub-skills/migrate | User provides a legacy skill directory, monolithic skill content, or a migration request | Load the legacy skill package, identify behaviors that must be preserved, propose function boundaries and evidence | migration_context |
Sub-skills do not directly write final target skill files. Their output must go through normalize_skill_blueprint before entering the shared artifact pipeline.
References
| Resource | Load Timing | Purpose |
|---|---|---|
shared_glossary | On demand | Stable terminology and cross-lane field semantics. |
script_rules | Before designing or drafting scripts | Rules for deciding whether deterministic work belongs in scripts/. |
sub-skills/create | Create lane | Form create_context from user brief. |
sub-skills/migrate | Migrate lane | Form migration_context from a legacy skill directory. |
External Inputs
| Field | Source | Description |
|---|---|---|
task_mode | user or derived | create, migrate, enhance, or validate; inferred by resolve_task_mode when absent. |
skill_request | user | Requirement description for creating or enhancing a skill. |
legacy_skill_dir | user or repository | Path to an existing legacy skill directory containing SKILL.md and optional companion files. |
legacy_skill_path | user or repository | Deprecated alias for legacy_skill_dir; may also be a direct path to SKILL.md, which resolves to its parent directory. |
legacy_skill_content | user | Legacy skill markdown provided when the path is inaccessible. |
target_skill_path | user or derived | Directory where the functional skill should live. |
skill_name | user or derived | Optional target skill name. |
existing_skill_files | repository | Optional existing functional skill files. |
migration_constraints | user | File names, tone, platform rules, or behaviors that must be preserved during migration. |
known_testcases | user or repository | Existing examples, traces, or expected behaviors. |
existing_scripts | repository | Helper scripts associated with the legacy skill. |
include_report | user | Whether to generate report log runtime in the target skill; defaults to true. |
include_unittest | user | Whether to generate unittest / testcase runner in the target skill; defaults to true. |
script_runtime | environment | Whether this skill's own Node.js scripts can be run. |
report_mode | user | off, local, or remote; defaults to off. |
Viewers are generated following the capability flags: tools/log_viewer.mjs when include_report=true; tools/tester_viewer.mjs when include_unittest=true.
Execution Pipeline
| Step | Function | Purpose | Input | Output |
|---|---|---|---|---|
| 1 | resolve_task_mode | Determine whether this request should go through create, migrate, enhance, or validate. | task_mode<br>skill_request<br>legacy_skill_dir<br>legacy_skill_path<br>legacy_skill_content<br>existing_skill_files | task_context |
| 2A | sub-skills/create::collect_create_brief | Create/enhance lane: normalize user brief. | skill_request<br>target_skill_path<br>skill_name | create_context |
| 2B | sub-skills/migrate::load_legacy_skill + map_existing_behavior + propose_function_split + extract_shared_references | Migrate lane: read the legacy skill package, extract behaviors and migration evidence. | legacy_skill_dir<br>legacy_skill_path<br>legacy_skill_content<br>migration_constraints<br>include_report<br>include_unittest<br>script_runtime | migration_context |
| 3 | normalize_skill_blueprint | Converge create / migrate / enhance inputs into a unified blueprint. | task_context<br>create_context<br>migration_context<br>target_skill_path<br>include_report<br>include_unittest | skill_blueprint |
| 4 | design_skill_structure | Design function pipeline, references, scripts, testcases, and file layout based on blueprint. | skill_blueprint<br>existing_skill_files<br>script_rules | skill_structure<br>script_plan<br>tool_plan |
| 5 | draft_skill_artifacts | Draft SKILL.md, function contracts, references, script specs, and testcase suggestions. | skill_blueprint<br>skill_structure<br>script_plan | skill_artifacts |
| 6 | add_runtime_capabilities | Provision report log, runtime wrapper, unit testcase runner, viewer, and smoke tests according to include flags. | skill_blueprint.include_report<br>skill_blueprint.include_unittest<br>skill_artifacts | runtime_artifacts<br>skill_artifacts |
| 7 | assemble_skill_files | Generate or update target skill directory files. | target_skill_path<br>skill_structure<br>skill_artifacts<br>runtime_artifacts<br>script_runtime | file_plan<br>created_files<br>updated_files |
| 8 | validate_skill | Validate functional-skill structure, runtime capabilities, testcases, and migration behavior preservation. | target_skill_path<br>file_plan<br>skill_blueprint<br>report_mode | validation_result |
Output Scope
This skill may read legacy skills and create or modify functional skill files under target_skill_path. Do not delete the original legacy skill unless the user explicitly requests deletion; do not modify unrelated repository files unless the user explicitly requests project-level integration.
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