name: github-discovery description: "Discover code, repositories, and perform PR reviews using GitHub API and CLI" requires: tools: [execute_command] interpreters: [python, bash] cli: [gh, jq]

GitHub Discovery & PR Review Skill

Automate GitHub code discovery, repository exploration, and pull request review workflows using GitHub API and CLI.

GitHub API Docs: docs.github.com/en/rest
GitHub CLI: cli.github.com

Prerequisites

• GitHub CLI (gh) - Required for all operations
• jq - JSON processor for parsing API responses
• Python 3.x - For fetching file contents
• GitHub Authentication - Run gh auth login

Installation

# Install GitHub CLI
# Mac: brew install gh
# Windows: winget install GitHub.cli
# Linux: See https://github.com/cli/cli#installation

# Install jq
# Mac: brew install jq
# Windows: winget install jqlang.jq
# Linux: apt-get install jq  or  yum install jq

# Authenticate
gh auth login

Use Cases

1. Code Discovery & Investigation

Find existing implementations before coding:

• Search for code patterns across GitHub
• Find similar implementations
• Discover best practices
• Reuse proven solutions

2. Repository Exploration

Research frameworks and libraries:

• Search repositories by technology
• Compare options by stars/activity
• Read documentation from repos
• Extract specific files for analysis

3. Pull Request Review

Comprehensive code review workflow:

• Extract complete PR context (diff, comments, reviews)
• Analyze changes for potential issues
• Generate review comments
• Suggest fixes and improvements
• Post reviews back to GitHub

Quick Start

Workflow 1: Search for Existing Implementation

# Step 1: Search for code implementing a feature
bash scripts/gh_search_code.sh "OAuth authentication implementation" 20

# Step 2: Search for related repositories
bash scripts/gh_search_repos.sh "language:python oauth" 15

# Step 3: Fetch a promising file to analyze
python fetch_github_api.py <owner> <repo> src/auth/oauth.py

Workflow 2: Pull Request Review

# Step 1: Extract complete PR context
bash scripts/gh_pr_review_context.sh facebook react 12345 > pr_context.txt

# Step 2: Claude analyzes the context (automatically)
# - Reviews diff for issues
# - Checks if comments are addressed
# - Suggests improvements

# Step 3: Post review comment
gh pr comment 12345 --repo facebook/react --body "Suggested fix: ..."

# Step 4: Submit full review
gh pr review 12345 --repo facebook/react --comment --body "Overall LGTM with minor suggestions"

Workflow 3: Branch Comparison & Review

# Compare two branches
gh api "/repos/{owner}/{repo}/compare/main...feature-branch" | jq '.'

# Get diff for review
gh pr diff <pr_number> --repo <owner>/<repo>

Scripts Reference

1. Code Search

Script: scripts/gh_search_code.sh

Purpose: Search across all GitHub code

Usage:

bash scripts/gh_search_code.sh <query> [limit]

Examples:

# Search for specific code pattern
bash scripts/gh_search_code.sh "class UserService" 20

# Search in specific language
bash scripts/gh_search_code.sh "language:python async def main" 30

# Search for React hooks implementation
bash scripts/gh_search_code.sh "useState useEffect" 50

Output: Repository name, file path, code matches, URL

2. Repository Search

Script: scripts/gh_search_repos.sh

Purpose: Find repositories by criteria

Usage:

bash scripts/gh_search_repos.sh <query> [limit]

Examples:

# Find Spring Boot projects
bash scripts/gh_search_repos.sh "spring boot" 20

# Find Python ML libraries
bash scripts/gh_search_repos.sh "language:python machine-learning" 30

# Find popular React frameworks
bash scripts/gh_search_repos.sh "language:javascript react stars:>1000" 15

Output: Repository name, stars, language, description, last update

3. Fetch File Content

Scripts: fetch_github_api.py | fetch_github_api.sh

Purpose: Get file contents from any GitHub repository

Usage:

# Python version (feature-rich)
python fetch_github_api.py <owner> <repo> <path> [--ref branch] [-o file]

# Shell version (lightweight)
bash fetch_github_api.sh -o <owner> -r <repo> -p <path> [-b branch] [-f file]

Quick Examples:

# Fetch README
python fetch_github_api.py spring-projects spring-framework README.md
bash fetch_github_api.sh -o spring-projects -r spring-framework -p README.md

# Save to file
python fetch_github_api.py owner repo src/Main.java -o Main.java
bash fetch_github_api.sh -o owner -r repo -p src/Main.java -f Main.java

4. PR Review Context Extraction

Script: scripts/gh_pr_review_context.sh

Purpose: Extract complete PR information for review

Usage:

bash scripts/gh_pr_review_context.sh <owner> <repo> <pr_number>

Example:

# Extract PR #12345 from facebook/react
bash scripts/gh_pr_review_context.sh facebook react 12345 > pr_review.txt

Output Includes:

• PR metadata (title, author, labels, status)
• List of changed files
• Complete diff
• Existing comments (general)
• Review comments (on specific lines)
• Reviews (approve/request changes/comment)
• Suggested next steps

Integration with Other Skills

Investigation: Search GitHub before implementing (see skills/investigation/SKILL.md)
Review: GitHub PR review workflow (see skills/review/SKILL.md)

API Reference

Complete documentation: github-api-docs-links.md (40+ categories, all endpoints)

Key endpoints: Search, PRs, Repos, Git Data, Reviews (see github-api-docs-links.md for details)

Best Practices

✅ Specific search queries: "class UserService implements" > "user"
✅ Filter by qualifiers: language:python, stars:>100, filename:package.json
✅ Extract complete PR context: Use gh_pr_review_context.sh
✅ Review systematically: Security → Logic → Performance → Style
✅ Respect rate limits: 5000/hour authenticated, 30/min for search
✅ Use gh CLI: Auto-handles auth, use shell scripts for lightweight ops

Rate Limits

• Authenticated: 5000/hour, Search: 30/min
• Unauthenticated: 60/hour, Search: 10/min
• Check status: gh api rate_limit

Troubleshooting

Auth issues: gh auth status → gh auth login
Rate limits: gh api rate_limit → wait or authenticate
Missing jq: brew install jq (Mac), apt-get install jq (Linux), winget install jqlang.jq (Windows)

Quick Reference

GitHub API Docs: https://docs.github.com/en/rest
GitHub CLI Docs: https://cli.github.com/manual/
API Reference: github-api-docs-links.md
Scripts: scripts/

Tip: Always reference github-api-docs-links.md when updating or adding new scripts to ensure you're using the latest API endpoints and best practices.