Create GitHub PR from Jujutsu Change

This skill enables creating GitHub pull requests from jj changes with automatically generated PR descriptions based on the diff.

Permission Requirements

CRITICAL: This workflow requires jj and gh CLI access with authentication. Always use:

required_permissions: ["all"]

Workflow

When the user asks to create a PR (e.g., "create a PR", "push for review", "open PR for @-"):

Step 1: Identify the Change

Default to @- (parent of working copy) unless the user specifies a different change.

# Get the change ID being pushed
jj log -r <change> --no-graph -T 'change_id ++ "\n"' | head -1

Step 2: Get PR Title

Extract the first line of the change's description:

jj log -r <change> -T description --no-graph | head -1

If empty, use a default like "Update from jj change".

Step 3: Analyze the Diff

Get the diff to understand what changed:

jj diff -r <change>

Step 4: Generate PR Description

Based on the diff, write a concise PR description:

• Summary: One sentence describing the overall change
• Changes: Bullet points of key modifications
• Keep it brief and focused on "what" and "why"
• Do not list every line change—summarize meaningfully

Example format:

## Summary
Brief description of what this PR accomplishes.

## Changes
- Added X to handle Y
- Refactored Z for better performance
- Fixed bug where A caused B

Step 5: Push the Change

jj git push -c <change>

Parse the branch name from output. Look for patterns:

• Creating bookmark <branch> or Add bookmark <branch>
• Move sideways bookmark <branch> from

Fallback if not found:

jj log -r <change> -T 'bookmarks' --no-graph

Step 6: Get Default Branch

gh repo view --json defaultBranchRef --jq '.defaultBranchRef.name'

Fallback to main if unavailable.

Step 7: Create the PR

gh pr create \
  --base <default_branch> \
  --head <branch_name> \
  --title "<pr_title>" \
  --body "<generated_description>" \
  --assignee @me

Complete Example

User: "Create a PR for @-"

# 1. Get title
jj log -r @- -T description --no-graph | head -1
# Output: "feat: add user authentication"

# 2. Get diff
jj diff -r @-
# (analyze the output)

# 3. Push change
jj git push -c @-
# Output: "Creating bookmark push-abc123..."

# 4. Get default branch
gh repo view --json defaultBranchRef --jq '.defaultBranchRef.name'
# Output: "main"

# 5. Create PR with generated description
gh pr create \
  --base main \
  --head push-abc123 \
  --title "feat: add user authentication" \
  --body "## Summary
Adds JWT-based user authentication to the API.

## Changes
- Added auth middleware for token validation
- Created login and register endpoints
- Added user model with password hashing" \
  --assignee @me

PR Description Guidelines

When generating the description:

1. Be concise: 3-5 bullet points max for most PRs
2. Focus on impact: What does this change enable or fix?
3. Skip obvious details: Don't mention formatting or trivial changes
4. Use present tense: "Adds X" not "Added X"
5. Group related changes: Combine related file changes into one point

Error Handling

• If push fails, report the error and stop
• If branch name cannot be determined, show the push output for debugging
• If PR creation fails (e.g., PR already exists), suggest gh pr view to see existing PR