Pr Review

All tools you need are already installed. Do not run pip install, apt-get, or any other installation commands. If a tool is missing, state that it is unavailable and move on.

Permissions

What You MUST NOT Do

• Commit or push — You have read-only access to repo contents. Never attempt git commit, git push, or create branches.
• Merge or close PRs — You cannot and should not merge pull requests.
• Install packages — Everything needed is pre-installed. Do not run pip install, npm install, apt-get, etc.
• Modify workflow files — Do not suggest changes to .github/workflows/ files in automated comments.
• Create issues — Do not open new GitHub issues.
• Assign users — Do not assign issues or PRs to specific people.

What You CAN Do

• Read all repo files — Full checkout is available at the workspace root.
• Run lintrunner — lintrunner -m main or lintrunner --all-files are available.
• Run make (dry/noplot) — make html-noplot works for RST/Sphinx validation (no GPU).
• Comment on PRs — Post review comments, inline suggestions, and general comments.

MCP Tools

Trigger & Interaction

Claude is invoked when a user mentions @claude in a PR comment or PR review comment. The triggering comment is passed as the prompt. Respond directly to what the user asked — do not perform unrequested actions.

• You are responding asynchronously via GitHub comments. There is no interactive terminal session.
• Be concise — GitHub comments should be scannable, not walls of text.
• Use markdown formatting (headers, tables, code blocks) for readability.
• If you cannot complete a request due to permission constraints, explain what you tried and what the user should do instead.

Usage Modes

No Argument

If the user invokes /pr-review with no arguments, do not perform a review. Instead, ask the user what they would like to review:

What would you like me to review?

• A PR number or URL (e.g., /pr-review 12345)
• A local branch (e.g., /pr-review branch)

Local CLI Mode

The user provides a PR number or URL:

/pr-review 12345
/pr-review https://github.com/pytorch/tutorials/pull/12345

For a detailed review with line-by-line specific comments:

/pr-review 12345 detailed

Use gh CLI to fetch PR data:

# Get PR details
gh pr view <PR_NUMBER> --json title,body,author,baseRefName,headRefName,files,additions,deletions,commits

# Get the diff
gh pr diff <PR_NUMBER>

# Get PR comments
gh pr view <PR_NUMBER> --json comments,reviews

Local Branch Mode

Review changes in the current branch that are not in main:

/pr-review branch
/pr-review branch detailed

Use git commands to get branch changes:

# Get current branch name
git branch --show-current

# Get list of changed files compared to main
git diff --name-only main...HEAD

# Get full diff compared to main
git diff main...HEAD

# Get commit log for the branch
git log main..HEAD --oneline

# Get diff stats (files changed, insertions, deletions)
git diff --stat main...HEAD

For local branch reviews:

• The "Summary" should describe what the branch changes accomplish based on commit messages and diff
• Use the current branch name in the review header instead of a PR number
• All other review criteria apply the same as PR reviews

GitHub Actions Mode

When invoked via workflow, PR data is passed as context. The PR number or diff will be available in the prompt. See the CI Environment section above for constraints and available tools.

Review Workflow

Step 1: Fetch PR Information

For local mode, use gh commands to get:

1. PR metadata (title, description, author)
2. List of changed files
3. Full diff of changes
4. Existing comments/reviews

Step 2: Analyze Changes

Read through the diff systematically:

1. Identify the purpose of the change from title/description
2. Group changes by type (tutorial content, config, build, infra)
3. Note the scope of changes (files affected, lines changed)

Step 3: Deep Review

Perform thorough analysis using the review checklist. See review-checklist.md for detailed criteria covering:

• Tutorial content quality and accuracy
• Code correctness in tutorial examples
• Sphinx/RST formatting
• Build compatibility
• Project structure compliance

Step 4: Formulate Review

Structure your review with actionable feedback organized by category.

Review Areas

Output Format

Structure your review as follows:

## PR Review: #<number>
<!-- Or for local branch reviews: -->
## Branch Review: <branch-name> (vs main)

### Summary
Brief overall assessment of the changes (1-2 sentences).

### Content Quality
[Issues and suggestions, or "No concerns" if none]

### Code Correctness
[Issues with tutorial code examples, imports, API usage, or "No concerns"]

### Structure & Formatting
[File placement, RST/Sphinx issues, index/toctree entries, or "No concerns"]

### Build Compatibility
[Dependency issues, data download concerns, CI compatibility, or "No concerns"]

### Recommendation
**Approve** / **Request Changes** / **Needs Discussion**

[Brief justification for recommendation]

Specific Comments (Detailed Review Only)

Only include this section if the user requests a "detailed" or "in depth" review.

Do not repeat observations already made in other sections. This section is for additional file-specific feedback that doesn't fit into the categorized sections above.

When requested, add file-specific feedback with line references:

### Specific Comments
- `beginner_source/my_tutorial.py:42` - Docstring prose is unclear; rephrase for non-native speakers
- `index.rst:150` - Missing customcarditem entry for the new tutorial
- `requirements.txt:30` - New dependency should be pinned to a specific version

Key Principles

1. No repetition - Each observation appears in exactly one section
2. Focus on what CI cannot check - Don't comment on trailing whitespace or tab characters (caught by lintrunner). RST syntax, Sphinx directives, and Python code style must still be reviewed
3. Be specific - Reference file paths and line numbers
4. Be actionable - Provide concrete suggestions, not vague concerns
5. Be proportionate - Minor issues shouldn't block, but note them
6. Audience awareness - Tutorials are read by beginners; clarity matters more than brevity

Files to Reference

When reviewing, consult these project files for context:

• CLAUDE.md - Project structure and coding style
• CONTRIBUTING.md - Submission process, tutorial types, and authoring guidance
• conf.py - Sphinx Gallery configuration and extensions
• requirements.txt - Approved dependencies
• index.rst - Card listings and toctree structure