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; unchanged content is never touched, and each regenerated instruction cites code by file:line. Stack skills (skill_type: "stack" in metadata.json) are not updated here: this workflow redirects them to skf-create-stack-skill, which re-composes them from updated constituents.

Conventions

• Bare paths (e.g. references/<name>.md) resolve from the skill root.
• Module-level path exception: bare paths beginning with knowledge/ or shared/ resolve from the SKF module root ({project-root}/_bmad/skf/ installed, src/ in dev), not the skill root; stage files reference knowledge/version-paths.md and knowledge/tool-resolution.md, and the terminal step chains to shared/health-check.md.
• Sibling skills: a path that names another SKF skill's folder (skf-<name>/...) resolves from the SKF module root, and that skill must be installed with this one.
• references/ holds the workflow stages, chained by each file's frontmatter nextStepFile (init.md §8 loads gap-driven.md through gapDrivenStepFile instead when update_mode is gap-driven), the [MANUAL] rules file merge.md loads, and the invocation contract; scripts/ holds this skill's own helper.
• {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 load shared assets from skf-create-skill, so create and update extract alike: re-extract.md pulls extraction-patterns.md, extraction-patterns-tracing.md and tier-degradation-rules.md from skf-create-skill/references/, detect-changes.md pulls extraction-patterns.md, and gap-driven.md pulls extraction-patterns.md and tier-degradation-rules.md; init.md §6c reads the version files the Version Reconciliation section of skf-create-skill/references/source-resolution-protocols.md lists, and skf-source-tree.py (init.md §6b) computes a remote skill's clone path with its workspace rule; write.md reads skill-sections.md from skf-create-skill/assets/, and extraction-patterns.md and, for §2's by-hand public API count, entry-points-by-hand.md from skf-create-skill/references/.

Role