Fskill Creator Agent Skill

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.md only 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 in sub-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.