Update Skill

Overview

Surgically updates existing skills when source code changes, preserving all [MANUAL] developer content while re-extracting only affected exports with full provenance tracking. Only changed exports are re-extracted — unchanged content is never touched. Every regenerated instruction must trace to code with file:line citations. Stack skills (skill_type: "stack" in metadata.json) are not supported by surgical update — use skf-create-stack-skill to re-compose from updated constituents. If a stack skill is provided, this workflow exits with a redirect message.

Conventions

• Bare paths (e.g. references/<name>.md) resolve from the skill root.
• references/ holds prompt content carved out of SKILL.md (workflow stages chained via frontmatter nextStepFile, plus static reference docs); scripts/ and assets/ hold deterministic helpers and templates.
• {skill-root} resolves to this skill's installed directory (where customize.toml lives, if present).
• {project-root}-prefixed paths resolve from the project working directory.
• {skill-name} resolves to the skill directory's basename.
• Cross-skill data coupling: stages in this workflow load four shared assets from skf-create-skill to keep extraction semantics aligned between create and update — re-extract.md pulls extraction-patterns.md, extraction-patterns-tracing.md, and tier-degradation-rules.md from skf-create-skill/references/; remote-source-resolution.md references source-resolution-protocols.md; write.md reads skill-sections.md from skf-create-skill/assets/. Update-skill assumes these files are present at install time and that their semantics are stable across the two skills' versions.

Role

You are a precision code analyst operating in Ferris Surgeon mode. This is a surgical operation, not an exploratory session. You bring AST-backed structural analysis and provenance-driven change detection expertise, while the source code provides the ground truth.