grep-app-cli

name	grep-app-cli
description	Search public GitHub code with the grep.app MCP CLI to find real implementation patterns, concrete API usage, regex-based code matches, and repository-scoped examples. Use when a task needs literal code search rather than documentation search, especially to verify how libraries, frameworks, config files, or language features are used in real projects.
license	MIT
compatibility	Requires uv and access to the internet
allowed-tools	Bash(uv run --with fastmcp python ./scripts/grep-app-mcp.py:*) Bash(sh ./scripts/grep-app-mcp.sh:*)
metadata	{"author":"knopki <[e-mail]>","version":"1.0.1","hermes":{"category":"research","complexity":"intermediate","icon":"🔍","tags":["code-search","github","mcp","grep.app"],"requires_toolsets":["terminal"]}}

grep.app CLI

Use this skill to query mcp.grep.app from the terminal and inspect real code from public repositories.

Workflow

1. Translate the user's need into a literal code pattern that would actually appear in source files.
2. Start with the narrowest useful query.
3. Add filters for --language, --repo, or --path before broadening the pattern.
4. Use --use-regexp only when a literal string is too restrictive.
5. Summarize the returned pattern and why it is relevant instead of dumping raw matches.

Query Design

• Search for code, not topics.
• Prefer tokens such as useState(, getServerSession, CORS(, server.listen(, FROM node:, or name: ci.
• Avoid natural-language queries such as react auth example or python cors tutorial.
• Keep the first pass short and exact; broaden only if the result set is empty or obviously too narrow.

Filter Strategy

• Use --language when syntax or framework usage is language-specific.
• Use --repo when the user asks about a known project, organization, or ecosystem.
• Use --path when the pattern is expected in files like package.json, Dockerfile, .github/workflows/, or /route.ts.
• Combine filters before switching to regex. Narrowing scope is usually cheaper than making the pattern more complex.

Regex Guidance

• Add --use-regexp for flexible patterns, optional spacing, or multi-line matches.
• Prefix with (?s) when the match may span line breaks.
• Escape regex metacharacters when the intent is literal punctuation.
• Prefer targeted regex such as (?s)useEffect\\(\\(\\) => \\{.*removeEventListener over overly broad .* searches with no anchors.

Commands

Resolve paths from the skill directory when invoking the bundled script.

cd skills/grep-app-cli
sh ./scripts/grep-app-mcp.sh list-tools

cd skills/grep-app-cli
sh ./scripts/grep-app-mcp.sh call-tool searchGitHub \
  --query "useState(" --language TSX --language TypeScript

cd skills/grep-app-cli
sh ./scripts/grep-app-mcp.sh call-tool searchGitHub \
  --query "(?s)try \\{.*await" --use-regexp --language Python

Supported Operations

• list-tools
• list-resources
• read-resource <uri>
• list-prompts
• get-prompt <name> [key=value ...]
• call-tool searchGitHub --query <pattern> [filters...]

searchGitHub Flags

• --query: required literal code pattern or regex.
• --match-case: use for case-sensitive identifiers or formats.
• --match-whole-words: use when partial identifier matches create noise.
• --use-regexp: enable regex interpretation.
• --repo: restrict to a repository or org fragment such as vercel/.
• --path: restrict to a file path or fragment such as /route.ts.
• --language: repeatable language filter such as --language TypeScript --language TSX.

Output Expectations

• Explain what pattern was searched and why.
• Call out any filters that materially shaped the result.
• Distinguish direct matches from your inference about best practice.
• Mention when results are sparse, noisy, or biased toward a specific ecosystem.

Limits

• Treat grep.app as a source of implementation examples, not as authoritative documentation.
• Do not claim a pattern is recommended solely because it appears in public repositories.
• Prefer official docs when the task depends on guarantees, specs, or version-specific behavior.