github-url-intercept

GitHub URL Intercept

CRITICAL: This skill activates AUTOMATICALLY when you see ANY github.com URL. Do NOT use web_fetch, curl, or any browser-based fetch on GitHub URLs. Doing so wastes 1-2.5 MILLION tokens on HTML that provides no useful data.

MANDATORY BEHAVIOR: Parse the URL → Route to API → Return structured JSON.

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Quick Reference (Copy-Paste Commands)

When you see a GitHub URL, use these commands immediately:

SCRIPTS_DIR="${CLAUDE_PLUGIN_ROOT:-.claude}/skills/github/scripts"

# PR URL → Use this
python3 "$SCRIPTS_DIR/pr/get_pr_context.py" --pull-request {n} --owner {owner} --repo {repo}

# Issue URL → Use this
python3 "$SCRIPTS_DIR/issue/get_issue_context.py" --issue {n} --owner {owner} --repo {repo}

# File/blob URL → Use this
gh api repos/{owner}/{repo}/contents/{path}?ref={ref}

# Commit URL → Use this
gh api repos/{owner}/{repo}/commits/{sha}

# Comment fragment (#discussion_r{id}) → Use this
gh api repos/{owner}/{repo}/pulls/comments/{id}

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Triggers

Phrase	Action
Any github.com URL in user input (even bare URL pasted alone)	Parse URL type and route to API
analyze / research / scan + GitHub URL	Route based on URL type
URL + question (e.g., "...#r123 what's the tracking issue?")	Extract fragment, call specific API
Multiple GitHub URLs in one prompt	Process each URL, batch API calls

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When to Use

Use this skill when:

• Any github.com URL appears in user input (automatic activation)
• User pastes a PR, issue, commit, file, or actions URL
• User asks to "analyze" or "review" a GitHub link

Use github instead when:

• Performing mutations (creating PRs, posting comments, adding labels)
• Operating on the current repository without a URL

URL Patterns (Detailed Reference)

Pattern	Example	Why Intercept
github.com/.../pull/	https://github.com/owner/repo/pull/123	PR HTML is 5-10MB
github.com/.../pull/.../checks	https://github.com/owner/repo/pull/123/checks?check_run_id=...	CI checks page bloat
github.com/.../pull/.../files or /changes	https://github.com/owner/repo/pull/123/files#r123456	Diff view with comment fragment
github.com/.../issues/	https://github.com/owner/repo/issues/456	Issue HTML is 2-5MB
github.com/.../actions/runs/	https://github.com/owner/repo/actions/runs/123/job/456	Workflow run page bloat
github.com/.../blob/	https://github.com/owner/repo/blob/main/file.py	File page has nav bloat
github.com/.../tree/	https://github.com/owner/repo/tree/main/src	Directory listing bloat
github.com/.../commit/	https://github.com/owner/repo/commit/abc123	Commit page overhead
github.com/.../compare/	https://github.com/owner/repo/compare/main...feat	Diff page overhead
github.com/.../discussions/	https://github.com/owner/repo/discussions/789	Discussion page bloat
Fragment #discussion_r{id}	Review comment ID in /changes or /files URL	Extract ID, call API directly
Fragment #issuecomment-{id}	Issue comment ID	Extract ID, call API directly
Fragment #pullrequestreview-{id}	Review ID	Extract ID, call API directly
Fragment #r{id} (short form)	Review comment in /changes#r123	Same as #discussion_r{id}

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Decision Flow

GitHub URL detected in user input
│
├─ Has fragment (#pullrequestreview-, #discussion_r, #issuecomment-)?
│     Yes → Extract ID, use gh api for specific comment/review
│
├─ Is /pull/{n}?
│     Yes → get_pr_context.py --pull-request {n} --owner {o} --repo {r}
│           (or get_pr_review_comments.py / get_pr_review_threads.py for comments)
│
├─ Is /issues/{n}?
│     Yes → get_issue_context.py --issue {n} --owner {o} --repo {r}
│
├─ Is /blob/{ref}/{path} or /tree/{ref}/{path}?
│     Yes → gh api repos/{o}/{r}/contents/{path}?ref={ref}
│
├─ Is /commit/{sha}?
│     Yes → gh api repos/{o}/{r}/commits/{sha}
│
└─ Is /compare/{base}...{head}?
      Yes → gh api repos/{o}/{r}/compare/{base}...{head}

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Process

Phase 1: URL Detection and Parsing

Step	Action	Verification
1.1	Detect github.com URL in user input	URL pattern matched
1.2	Extract owner/repo from path	Both values non-empty
1.3	Identify URL type (pull, issues, blob, tree, commit, compare)	Type classified
1.4	Extract fragment ID if present	Fragment parsed or null

Phase 2: Route Selection

Step	Action	Verification
2.1	Check if github skill script exists for URL type	Script path resolved
2.2	If script exists → use github skill (primary route)	Script invocation planned
2.3	If no script → use gh api (fallback route)	API command constructed
2.4	For fragments → always use gh api with specific endpoint	Endpoint includes ID

Phase 3: Execution

Step	Action	Verification
3.1	Execute selected command	Command runs without error
3.2	Receive structured JSON response	Success: true for scripts
3.3	Parse relevant fields for user query	Response processed

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URL Routing Table

Primary: Use GitHub Skill Scripts

URL Pattern	Script	Parameters
/pull/{n}	get_pr_context.py	--pull-request {n} --owner {o} --repo {r}
/pull/{n} (with diff)	get_pr_context.py	--pull-request {n} --include-diff
/pull/{n} (review comments)	get_pr_review_comments.py	--pull-request {n}
/pull/{n} (review threads)	get_pr_review_threads.py	--pull-request {n}
/pull/{n} (CI status)	get_pr_checks.py	--pull-request {n}
/issues/{n}	get_issue_context.py	--issue {n} --owner {o} --repo {r}

Script location: .claude/skills/github/scripts/

Fallback: Raw gh Commands

Use only when no script exists for the operation:

URL Pattern	API Call
/pull/{n}#pullrequestreview-{id}	gh api repos/{o}/{r}/pulls/{n}/reviews/{id}
/pull/{n}#discussion_r{id}	gh api repos/{o}/{r}/pulls/comments/{id}
/pull/{n}/files#r{id} or /changes#r{id}	gh api repos/{o}/{r}/pulls/comments/{id}
/pull/{n}#issuecomment-{id}	gh api repos/{o}/{r}/issues/comments/{id}
/pull/{n}/checks	gh api repos/{o}/{r}/check-runs?head_sha=... or use get_pr_checks.py
/issues/{n}#issuecomment-{id}	gh api repos/{o}/{r}/issues/comments/{id}
/actions/runs/{run_id}	gh api repos/{o}/{r}/actions/runs/{run_id}
/actions/runs/{run_id}/job/{job_id}	gh api repos/{o}/{r}/actions/jobs/{job_id}
/blob/{ref}/{path}	gh api repos/{o}/{r}/contents/{path}?ref={ref}
/tree/{ref}/{path}	gh api repos/{o}/{r}/contents/{path}?ref={ref}
/commit/{sha}	gh api repos/{o}/{r}/commits/{sha}
/compare/{base}...{head}	gh api repos/{o}/{r}/compare/{base}...{head}

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URL Parsing Pattern

Extract owner, repo, and resource from GitHub URLs:

https://github.com/{owner}/{repo}/pull/{number}
https://github.com/{owner}/{repo}/issues/{number}
https://github.com/{owner}/{repo}/blob/{ref}/{path}
https://github.com/{owner}/{repo}/tree/{ref}/{path}
https://github.com/{owner}/{repo}/commit/{sha}
https://github.com/{owner}/{repo}/compare/{base}...{head}

Fragment extraction (when present):

• #pullrequestreview-{id} → Review ID
• #discussion_r{id} → Discussion comment ID
• #issuecomment-{id} → Issue comment ID

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Why This Matters (CRITICAL)

Fetching GitHub HTML is catastrophic for your context window:

Method	Response Size	Token Cost	Time	Usability
❌ HTML fetch	5-10 MB	1-2.5M tokens	10-30s	UNUSABLE - HTML noise, no structured data
✅ API call	1-50 KB	250-12K tokens	0.5-2s	Clean JSON with exactly what you need
✅ Script	1-50 KB	250-12K tokens	0.5-2s	Structured output, error handling

Impact: 100-1000x reduction in token consumption.

If you fetch GitHub HTML directly, you will:

1. Consume your entire context window on ONE page
2. Get no useful structured data (just HTML soup)
3. Be unable to process subsequent user requests
4. Need to start a new conversation

ALWAYS use this skill when you see a GitHub URL.

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Examples

Bare URL Pasted (Most Common!)

Input: "https://github.com/rjmurillo/ai-agents/pull/735/checks?check_run_id=59355308734"

Action:
  1. Parse: owner=rjmurillo, repo=ai-agents, pr=735, type=checks
  2. Route: python3 "$SCRIPTS_DIR/pr/get_pr_checks.py" --pull-request 735 --owner rjmurillo --repo ai-agents

URL with Question After It

Input: "https://github.com/owner/repo/pull/715/changes#r2656144507 are the graph refactoring items part of Issue 722?"

Action:
  1. Extract fragment: r2656144507 (review comment ID)
  2. Call: gh api "repos/owner/repo/pulls/comments/2656144507"
  3. Answer user's question using the comment content

Multiple URLs in One Prompt

Input: "https://github.com/owner/repo/pull/715#discussion_r123 https://github.com/owner/repo/pull/715#discussion_r456"

Action:
  1. Parse each URL
  2. Batch: gh api "repos/owner/repo/pulls/comments/123"
  3. Batch: gh api "repos/owner/repo/pulls/comments/456"

Research/Analyze Pattern

Input: "analyze https://github.com/modu-ai/moai-adk for insights"

Action:
  1. Use deepwiki MCP or gh api to get repo info
  2. Call: gh api "repos/modu-ai/moai-adk" (NOT web_fetch!)

CI/Actions Run URL

Input: "https://github.com/owner/repo/actions/runs/20675405338/job/59362398542?pr=740"

Action:
  1. Extract: run_id=20675405338, job_id=59362398542
  2. Call: gh api "repos/owner/repo/actions/jobs/59362398542"

PR URL → Script

Input: "Review this: https://github.com/owner/repo/pull/123"

Action:
  python3 "$SCRIPTS_DIR/pr/get_pr_context.py" --pull-request 123 --owner owner --repo repo

File URL → API

Input: "would a hook like https://github.com/ruvnet/claude-flow/blob/main/.claude/settings.json help?"

Action:
  gh api "repos/ruvnet/claude-flow/contents/.claude/settings.json?ref=main"

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Anti-Patterns (NEVER DO THESE)

❌ NEVER	Why It's Catastrophic	✅ Do This Instead
web_fetch("https://github.com/...")	5-10 MB HTML, 1-2.5M tokens WASTED	Parse URL, use script or gh api
curl https://github.com/...	Same catastrophic result	Use gh CLI for authentication + JSON
fetch / requests.get on GitHub URLs	Same catastrophic result	Route through this skill
gh pr view without --json	Unstructured text output	Use get_pr_context.py for structured JSON
Fetching full page to find one comment	Fetches 5MB to read 500 bytes	Extract fragment ID (#discussion_r...), call specific endpoint
Ignoring GitHub URLs in user input	User expects you to understand the link	ALWAYS parse and route
Hardcoding owner/repo in commands	Breaks when user shares fork/different repo	Extract from URL path

RED FLAG PHRASES - If you're about to do any of these, STOP:

• "Let me fetch that page..."
• "I'll retrieve the content from that URL..."
• "Accessing the GitHub page..."

These indicate you're about to waste millions of tokens. Use this skill instead.

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Scripts

test_url_routing.py

Routes GitHub URLs to appropriate API access methods with CWE-78 command injection protection.

python3 .claude/skills/github-url-intercept/scripts/test_url_routing.py <github-url>

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Related Skills

Skill	When to Use
github	Full PR/issue operations (mutations, reactions, labels)
pr-comment-responder	Systematic PR review response

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Verification Checklist

Before processing any GitHub URL:

• Extracted owner/repo from URL path
• Identified URL type (PR, issue, blob, commit, compare)
• Extracted fragment ID if present (#discussion_r, #issuecomment-, #pullrequestreview-)
• Selected appropriate github skill script (primary) or gh command (fallback)
• Did NOT use web_fetch, curl, or browser-based fetch on the URL
• Received structured JSON response with Success: true (for scripts)