setup-indexing-skill

A greppable code-index installer as a skill for Claude Code (and any agent that supports skills — OpenCode, Codex, Cursor). Let agents locate files and symbols with one grep on one file instead of rescanning the whole project every session.

Survey → Install index.sh → Wire up (CLAUDE.md + hook) → Validate with measurements → Report

The skill generates an index.sh that emits, per repo (or per workspace member), a single markdown file at .claude/index/<member>.md with three sections — ## dirs, ## files, ## symbols (path:line:definition) — so an agent answers "where is X?" without fanning Glob/Grep/Read across the tree.

Measured on a real multi-repo workspace: same accuracy as free exploration, ~30% less context processed, ~40% less wall time, zero junk matches (worktree / vendored copies excluded by construction via git ls-files).

How it works

1. Surveys the project — single repo vs. multi-member workspace, submodules, languages present, existing ctags/LSP tooling.
2. Installs index.sh (from assets/index.sh.template) and wires /.claude/index/ into .gitignore. Covers TS/JS (incl. routes), Rust, Go, shell, Python, and shebang executables.
3. Wires it up — adds a CLAUDE.md section so every session greps the index first, plus an optional SessionStart hook to auto-refresh in seconds.
4. Validates with measurements — syntax + full run, edge-case sandbox, a measured recall check (≥7/8 elements locatable via the index alone), staleness detection, optional A/B benchmark.
5. Reports — files installed, index sizes + generation time, validation table, what was skipped.

Runtime: stock macOS bash 3.2 + BSD tools under set -euo pipefail; works on Linux too. git ls-files (not find/rg) is what excludes worktrees, node_modules, and build output by construction.

Install

npx add-skill Gamma-Software/setup-indexing-skill           # all detected agents
npx add-skill Gamma-Software/setup-indexing-skill --global  # globally

Or manually:

git clone https://github.com/Gamma-Software/setup-indexing-skill.git
ln -s "$PWD/setup-indexing-skill" ~/.claude/skills/setup-indexing   # or copy it

Usage

Just ask — it auto-triggers ("set up code indexing", "the agent keeps re-scanning the repo", "make agent search faster", "give me a symbol index / code map") — or run /setup-indexing.

Agent	Global path	Project path
Claude Code	~/.claude/skills/setup-indexing/	.claude/skills/setup-indexing/
OpenCode	~/.config/opencode/skill/setup-indexing/	.opencode/skill/setup-indexing/
Codex	~/.codex/skills/setup-indexing/	.codex/skills/setup-indexing/
Cursor	~/.cursor/skills/setup-indexing/	.cursor/skills/setup-indexing/

Structure

setup-indexing-skill/
├── SKILL.md                  # the 5-step install+validate procedure
├── assets/
│   └── index.sh.template     # the index generator (copied into target project)
├── references/
│   └── validation.md         # the validation gates
└── evals/
    └── evals.json            # trigger evals

Requirements

• git, grep, sort, cut (stock POSIX / BSD tools)
• bash 3.2+

License

MIT