PR Research Skill

Systematic exploration of upstream repositories before contributing.

Overview

Research an external codebase to understand how to contribute effectively. This is the FIRST step before planning or implementing an open source contribution.

When to Use:

• Before contributing to an external repository
• Starting a new open source contribution
• Evaluating whether to contribute to a project

When NOT to Use:

• Researching your own codebase (use $research)
• Already familiar with the project's guidelines

---

Workflow

-1. Prior Work Check    -> BLOCKING: Check for existing issues/PRs
0.  CONTRIBUTING.md     -> MANDATORY: Find contribution guidelines
1.  Repository Setup    -> Clone/identify upstream repo
2.  Guidelines Analysis -> Templates, CODE_OF_CONDUCT
3.  PR Archaeology      -> Analyze merged PRs, commit patterns
4.  Maintainer Research -> Response patterns, review expectations
5.  Issue Discovery     -> Find contribution opportunities
6.  Output              -> Write research document

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Phase -1: Prior Work Check (BLOCKING)

CRITICAL: Before ANY research, check if someone is already working on this.

# Search for open issues on this topic
gh issue list -R <owner/repo> --state open --search "<topic keywords>" --limit 20

# Search for open PRs that might address this
gh pr list -R <owner/repo> --state open --search "<topic keywords>" --limit 20

# Check for recently merged PRs (might already be fixed)
gh pr list -R <owner/repo> --state merged --search "<topic keywords>" --limit 10

Finding	Action
Open issue exists	Link to it, don't create duplicate
Open PR exists	Don't duplicate work
Recently merged PR	Verify fix, no work needed
No prior work found	Proceed to Phase 0

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Phase 0: CONTRIBUTING.md Discovery (BLOCKING)

CRITICAL: Do not proceed without finding contribution guidelines.

# Check all common locations
cat CONTRIBUTING.md 2>/dev/null
cat .github/CONTRIBUTING.md 2>/dev/null
cat docs/CONTRIBUTING.md 2>/dev/null

# Check README for contribution section
grep -i "contribut" README.md | head -10

Extract Key Requirements

Requirement	Where to Find
Commit format	"Commit messages" section
PR process	"Pull Requests" section
Testing requirements	"Testing" section
Code style	"Style" section
CLA/DCO	"Legal" or "License" section

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Phase 3: PR Archaeology

CRITICAL: Understand what successful PRs look like.

# List recent merged PRs
gh pr list --state merged --limit 20

# Recent commit style
git log --oneline -30 | head -20

# Check for conventional commits
git log --oneline -30 | grep -E "^[a-f0-9]+ (feat|fix|docs|refactor|test|chore)(\(.*\))?:"

PR Size Analysis

Size	Files	Lines	Likelihood
Small	1-3	<100	High acceptance
Medium	4-10	100-500	Moderate
Large	10+	500+	Needs discussion first

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Phase 5: Issue Discovery

# Find beginner-friendly issues
gh issue list --label "good first issue" --state open
gh issue list --label "help wanted" --state open

# Issues with no assignee
gh issue list --state open --json assignees,title,number | \
  jq -r '.[] | select(.assignees | length == 0) | "#\(.number): \(.title)"' | head -10

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Output

Write to .agents/research/YYYY-MM-DD-pr-{repo-slug}.md

# PR Research: {repo-name}

## Executive Summary
{2-3 sentences: project health, contribution friendliness}

## Contribution Guidelines
| Document | Status | Key Requirements |
|----------|--------|------------------|
| CONTRIBUTING.md | Present/Missing | {summary} |
| PR Template | Present/Missing | {required sections} |

## PR Patterns
- **Average size**: X files, Y lines
- **Commit style**: {conventional/imperative/etc}
- **Review time**: ~X days

## Contribution Opportunities
| Issue | Type | Difficulty |
|-------|------|------------|
| #N | bug/feat | easy/medium |

## Next Steps
-> `$pr-plan .agents/research/YYYY-MM-DD-pr-{repo}.md`

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Anti-Patterns

DON'T	DO INSTEAD
Skip guidelines check	Always read CONTRIBUTING.md first
Ignore PR patterns	Study successful merged PRs
Start with large PRs	Begin with small, focused changes

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Workflow Integration

$pr-research <repo> -> $pr-plan <research> -> implement -> $pr-prep

Examples

Research Upstream Before Contributing

User says: "Do PR research for owner/repo before I propose a fix."

What happens:

1. Inspect contribution guidelines and governance files.
2. Analyze merged PR patterns and conventions.
3. Produce a research artifact with opportunities and risks.

Scope Discovery

User says: "Find small starter contribution options in this repo."

What happens:

1. Scan issues/labels and prior merged work.
2. Classify candidates by difficulty and scope.
3. Recommend a smallest-safe starting contribution.

Troubleshooting

Problem	Cause	Solution
No contribution guide found	Repo lacks standard files	Infer conventions from merged PR history and maintainers' comments
Too many possible issues	Scope not constrained	Filter by labels, component paths, and recent maintainer activity
Suggested work seems risky	Hidden dependency or broad blast radius	Downscope to narrower file/domain boundary and restate assumptions
Output is too generic	Insufficient repository evidence	Add concrete file/PR references and explicit pattern findings

Reference Documents

• references/upstream-research-checklist.md