Nm Leyline Sem Integration

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name: sem-integration description: | Foundation skill for sem (semantic diff CLI) integration. Provides detection, install-on-first-use, and output normalization patterns for consumer skills version: 1.9.4 triggers: - sem - semantic-diff - git - foundation metadata: {"openclaw": {"homepage": "https://github.com/athola/claude-night-market/tree/master/plugins/leyline", "emoji": "\ud83e\udd9e"}} source: claude-night-market source_plugin: leyline

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> Night Market Skill — ported from claude-night-market/leyline. For the full experience with agents, hooks, and commands, install the Claude Code plugin.

sem Integration

Foundation patterns for using sem semantic diffs in night-market skills.

When To Use

Consult this skill when building or modifying skills that consume git diff output. It provides the detection, installation, and fallback patterns.

When NOT To Use

Direct sem CLI usage (just run sem diff yourself)

Skills that don't consume diff output

Detection Pattern

Check sem availability once per session:

# Detection (cache per session)
_sem_check() {
  local cache="${CLAUDE_CODE_TMPDIR:-/tmp}/sem-available"
  if [ -f "$cache" ]; then
    cat "$cache"
    return
  fi
  if command -v sem &>/dev/null; then
    echo "1" | tee "$cache"
  else
    echo "0" | tee "$cache"
  fi
}

When _sem_check returns 0, offer installation. See modules/detection.md for install-on-first-use logic and platform-specific commands.

Semantic Diff Pattern

Primary path (sem available):

sem diff --json 

Fallback path (sem unavailable):

git diff --name-only --diff-filter=A 
git diff --name-only --diff-filter=M 
git diff --name-only --diff-filter=D 
git diff --name-only --diff-filter=R 

See modules/fallback.md for output normalization that produces the same entity schema from both paths.

Impact Analysis Pattern

Primary path (sem available):

sem impact --json 

Fallback path (sem unavailable): use rg/grep to trace callers by filename. See modules/fallback.md.