Sync skill between repos

---

description: "Compare and sync a skill from a source repo. Args: <skill-path> --from <repo-path> [--dry-run] [--meta] [--universal-only] [--include-commands] [--help]"

Sync a skill directory between repos, preserving repo-specific content.

1. Parse and validate

If --help is present, display help text and stop:

/sync-skill — Compare and sync a skill from a source repo.

Usage:
  /sync-skill <skill-path> --from <repo-path> [flags]
  /sync-skill --meta --from <repo-path> [flags]

Flags:
  --from <path>        Source repo path (required)
  --dry-run            Report only, no changes
  --meta               Sync the sync-skill itself
  --universal-only     Skip repo-specific zone diffs
  --include-commands   Also compare .claude/commands/ symlinks
  --help               Show this help

Examples:
  /sync-skill git --from ~/dotfiles
  /sync-skill git --from ~/dotfiles --dry-run
  /sync-skill --meta --from ~/dotfiles

Extract <skill-path> and --from <path> from $ARGUMENTS.

If --meta: set skill-path to .claude/skills/meta/ and also check .claude/commands/sync-skill.md. <skill-path> argument not required.

Validate source path exists: ls <from>/.claude/skills/<skill-path>/. If missing → error and stop.

Check if target exists: ls .claude/skills/<skill-path>/. If missing → new skill bootstrap (Step 1a).

Step 1a: New skill bootstrap

When the source has a skill that doesn't exist in the target:

1. Announce: "Skill <skill-path> exists in source but not in this repo."
2. List source files with brief description of each.
3. Classify each file:
   • Universal (no <!-- REPO-SPECIFIC --> markers): copy verbatim.
   • Parameterized (has markers): copy with repo-specific zones replaced by scaffold prompts.
4. Generate bootstrap plan showing:
   • Which files copied verbatim (universal)
   • Which files scaffolded (parameterized) — listing each zone
   • What symlinks to create in .claude/commands/
   • What CLAUDE.md entries to add
5. For each scaffolded zone, describe what the source has and what the target should provide. Example:

   workflow.md — REPO-SPECIFIC zones to customize:
   
   1. scopes: Source has tool-based scopes (nvim, tmux, brew...).
      → Define scopes for YOUR repo's content areas.
      → Look at your directory structure to decide groupings.
   
   2. examples: Source has dotfiles commit examples.
      → Write 3-5 commit examples reflecting YOUR repo's patterns.
      → Run `git log --oneline -20` for inspiration.
   

6. Wait for approval before creating any files.
7. After approval: create directory, copy/scaffold files, create symlinks.
8. Post-bootstrap: offer to fill repo-specific zones interactively: "Want me to analyze your repo and walk you through each zone?" If the user accepts, run the repo-specific zone survey (see Step 6a) for every scaffolded zone across all files.

2. Discover files

Use Glob on both directories to list all files recursively:

• Source: <from>/.claude/skills/<skill-path>/**/*
• Target: .claude/skills/<skill-path>/**/*

Classify by relative path:

• Both: exists in source and target
• Source-only: exists in source but not target
• Target-only: exists in target but not source

If --include-commands: also compare .claude/commands/ symlinks pointing into the skill directory.

3. Compare files in both repos

For each file present in both:

3a. Read both files

3b. Check for <!-- REPO-SPECIFIC: name --> markers

If markers exist:

• Parse into segments: alternating "universal" and "repo-specific" blocks.
• Universal = text outside marker pairs.
• Repo-specific = text between <!-- REPO-SPECIFIC: ... --> / <!-- END REPO-SPECIFIC --> pairs (inclusive).
• Compare only universal blocks between source and target.
• Identical → "in sync".
• Different → "universal drift detected". Show diff of universal blocks only.
• Always report repo-specific zones as "intentionally different (N zones)".
• If --universal-only: skip repo-specific zone reporting entirely.

If no markers:

• Diff the two files.
• Identical → "in sync".
• Different → flag as drift. Show full diff.
• Look for patterns suggesting repo-specific content (scope tables, path examples, tool names). Warn: "This file has no REPO-SPECIFIC markers. Consider adding them if some content should differ."

Unmatched markers: If open/close tags don't match, warn and fall back to full-file diff.

4. Generate sync report

========================================
Skill Sync Report: <skill-path>
========================================
Source: <from-path>
Target: <current-repo-path>
Date:   <today>

--- Files in sync (universal) ---
  commands/commit.md           identical
  flags.md                     identical
  land.md                      identical

--- Files with repo-specific zones ---
  workflow.md                  universal: IN SYNC | repo-specific: 6 zones (expected)
  emoji.md                     universal: IN SYNC | repo-specific: 1 zone (expected)

--- Universal drift detected ---
  (none)
  OR:
  workflow.md  lines 18-24:
    Source adds: "**REQUIRED**: When presenting..."
    Target has:  "When presenting a plan..."

--- Source-only files ---
  (none)  OR:
  new-feature.md               exists in source, not in target

--- Target-only files ---
  blog-overrides.md            exists in target only (repo-specific, expected)

========================================
Summary: 5 files checked, 3 identical, 2 repo-specific OK, 0 drift
========================================

If --dry-run: stop here. Do not generate a sync plan.

5. Generate sync plan

Default: plan-first. Generate a complete sync plan and wait for user approval before making any changes.

========================================
Sync Plan: <skill-path>
========================================
Source: <from-path>
Target: <current-repo-path>

Actions (in order):

1. UPDATE universal sections in workflow.md
   - Lines 18-24: "Feature Branches in Plans" → stronger REQUIRED language
   - Repo-specific zones (6): PRESERVED, no changes

2. COPY new file: guardrails.md
   - Universal file (no markers), copy verbatim from source

3. SKIP blog-overrides.md
   - Target-only file (repo-specific, no action needed)

4. NO ACTION needed for: commit.md, flags.md, land.md, emoji.md
   - Already in sync

========================================
Approve this plan? [approve / modify / abort]
========================================

User responses:

• approve: Execute all actions.
• modify: User specifies changes. Re-present plan.
• abort: Stop without changes.

6. Execute approved plan

UPDATE (universal drift):

• Read target file.
• For each universal block, replace with source's version.
• Repo-specific zones (between markers) left untouched.
• Write result.

COPY (source-only, no markers):

• Copy verbatim from source to target.

COPY-AND-SCAFFOLD (source-only, with markers):

• Copy from source.
• Replace repo-specific zone contents with:

  <!-- REPO-SPECIFIC: <name> -->
  <!-- TODO: Define <name> for this repo. See source for format. -->
  <!-- END REPO-SPECIFIC -->
  

• Present scaffolded file to user, then run the repo-specific zone survey (Step 6a) for each zone.

Step 6a: Repo-specific zone survey

When filling repo-specific zones — whether from bootstrap (Step 1a) or COPY-AND-SCAFFOLD — walk the user through each zone interactively:

1. Analyze the target repo — read directory structure, CLAUDE.md, git log --oneline -20, and any relevant config files to inform suggestions.
2. One zone at a time — for each <!-- REPO-SPECIFIC: <name> --> zone: a. Explain what this zone controls and show what the source repo has. b. Present suggested options as a checkbox list with a freeform option:

   Zone: scopes (workflow.md)
   Source has: nvim, tmux, brew, git, zsh, ...
   
   What scopes fit this repo?
   
   a. [ ] By directory (frontend, backend, infra, ...)
   b. [ ] By language (ts, py, go, ...)
   c. [ ] By concern (api, auth, db, ui, ...)
   d. [ ] Use source scopes as-is (they fit this repo too)
   e. [ ] Other — tell me what you have in mind
   

   c. Wait for the user's answer before moving to the next zone. d. After the answer, draft the zone content and confirm: "Here's what I'll write for <name> — approve or revise?"
3. After all zones complete — show the full file with all zones filled in for final approval before writing.

SKIP:

• No action.

7. Verify

After all changes applied:

• Re-run comparison (steps 2-4) and show updated report.
• Show git diff --stat of modified files.
• If COPY-AND-SCAFFOLD actions taken, remind user to fill TODO placeholders.
• Suggest: "Review changes, then /commit to save."

First-time sync: no markers yet

When syncing to a repo that has skill files but no REPO-SPECIFIC markers:

Detection: Step 3b finds no markers in either copy. Full diff computed.

Classification: Differences classified as:

• Likely repo-specific: Scope tables, branch name examples, path examples, commit examples, type description wording.
• Likely universal drift: Structural changes, new sections, rule changes.

Recommendation: The sync plan proposes:

1. Add REPO-SPECIFIC markers to source (if not already there).
2. Add matching markers to target, wrapping target's existing content.
3. Then compare universal sections.

Self-sync

/sync-skill --meta --from <path> compares the sync-skill's own files. sync-skill.md has no REPO-SPECIFIC markers (fully universal), so step 3b treats it as a plain diff.

Recommendation: When syncing multiple skills, self-sync first:

/sync-skill --meta --from ~/dotfiles
/sync-skill git --from ~/dotfiles