# gitnexus-impact-analysis

This skill maps what breaks when you change a function or file: direct callers, indirect dependencies and affected execution flows. Useful before touching unfamiliar code.

- skill · `type=skill` · Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, OpenCode · 1900 installs · ★ 48043
- Author: abhigyanpatwari
- License: LicenseRef-Unknown · policy=link-only · description only; the file stays with the author
- Source: https://github.com/abhigyanpatwari/GitNexus/tree/HEAD/gitnexus-claude-plugin/skills/gitnexus-impact-analysis/SKILL.md
- Updated: 2026-10-25
- HTML: https://affpapa.org/en/nevibecode/skills/gitnexus-impact-analysis

## What it does

The skill answers questions like whether it is safe to change a function and who calls it. It walks the dependency graph upstream and sorts results by depth: d=1 are direct callers that will break, d=2 are indirectly affected, d=3 may need testing. It also checks affected execution flows and recent edits through a git diff.

It runs through the MCP tools `impact` and `detect_changes`, with CLI fallbacks `node .gitnexus/run.cjs impact <symbol> --direction upstream --repo .` and `node .gitnexus/run.cjs detect-changes --scope all --repo .`. Before the first call the skill wants `list_repos {}` to bind the repository. Once more than one repository is indexed, `repo` is required on every call: with a default configured in the MCP policy an omitted `repo` resolves to that default silently, and the answer describes the wrong code. If the intended repository is unclear, the skill says to stop and ask.

Worktrees are the sharp edge. `detect_changes` takes `worktree` when your edits live in a linked worktree the MCP server was not started from: the server only auto-detects a worktree when launched inside one, otherwise `git diff` runs against another checkout and reports zero changed symbols. That zero looks exactly like a real clean result, so check that the diffed checkout is the one you edited. The `partial` and `truncated` flags mean the result is incomplete and the check should be re-run.

## Install

### Claude Code (native platform)

1. **Skills CLI (Vercel)**
```bash
npx skills add abhigyanpatwari/GitNexus --skill gitnexus-impact-analysis -a claude-code
```

2. **Manually: put the files in place**
- File: `~/.claude/skills/gitnexus-impact-analysis/SKILL.md` — Copy the whole skill folder; for one project use .claude/skills/gitnexus-impact-analysis/

### Codex

1. **Skills CLI (Vercel)**
```bash
npx skills add abhigyanpatwari/GitNexus --skill gitnexus-impact-analysis -a codex
```

2. **Manually: put the files in place**
- File: `.agents/skills/gitnexus-impact-analysis/SKILL.md` — For all projects use ~/.agents/skills/

### Cursor

1. **Skills CLI (Vercel)**
```bash
npx skills add abhigyanpatwari/GitNexus --skill gitnexus-impact-analysis -a cursor
```

2. **Manually: put the files in place**
- File: `.cursor/skills/gitnexus-impact-analysis/SKILL.md` — Cursor also reads .agents/skills/ and .claude/skills/

### GitHub Copilot

1. **GitHub CLI**
```bash
gh skill install abhigyanpatwari/GitNexus gitnexus-impact-analysis
```

2. **Manually: put the files in place**
- File: `.github/skills/gitnexus-impact-analysis/SKILL.md`

### Gemini CLI

1. **Skills CLI (Vercel)**
```bash
npx skills add abhigyanpatwari/GitNexus --skill gitnexus-impact-analysis -a gemini-cli
```

2. **Platform CLI**
```bash
gemini skills install https://github.com/abhigyanpatwari/GitNexus --path gitnexus-claude-plugin/skills/gitnexus-impact-analysis
```

### Windsurf (Devin Desktop)

**Manually: put the files in place**
- File: `.devin/skills/gitnexus-impact-analysis/SKILL.md` — The legacy .windsurf/skills/ path still works

### OpenCode

**Skills CLI (Vercel)**
```bash
npx skills add abhigyanpatwari/GitNexus --skill gitnexus-impact-analysis -a opencode
```

### Claude.ai

**Claude.ai**
- Zip the folder and upload it in Settings → Capabilities → Skills

Where a file is given instead of a command, copy the files from the source to that path: https://github.com/abhigyanpatwari/GitNexus/tree/HEAD/gitnexus-claude-plugin/skills/gitnexus-impact-analysis/SKILL.md

## When to use it
- find which callers break when a function changes
- size the blast radius before a refactor
- check affected execution flows
- run a pre-commit check on the git diff
- tell an unused symbol from one the index cannot resolve

## Example prompts
- What breaks if I change `validateUser`?
- Show me the blast radius for `apiMiddleware`
- Check my changes before I commit

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From the same set: [abhigyanpatwari/gitnexus](https://affpapa.org/en/nevibecode/by/abhigyanpatwari/gitnexus.md) — 8 cards

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