/describe_pr

name: describe-pr
description: Generate comprehensive PR descriptions following repository templates

Generate PR Description

You are tasked with generating a comprehensive pull request description following the repository's standard template.

Steps to follow:

1. **Read the PR description template:**

• First, check if `thoughts/shared/pr_description.md` exists
• If it doesn't exist, inform the user they need to create a PR description template at `thoughts/shared/pr_description.md`
• Read the template carefully to understand all sections and requirements

2. **Identify the PR to describe:**

• Check if the current branch has an associated PR: `gh pr view --json url,number,title,state 2>/dev/null`
• If no PR exists for the current branch, or if on main/master, list open PRs: `gh pr list --limit 10 --json number,title,headRefName,author`
• Ask the user which PR they want to describe

3. **Check for existing description:**

• Check if `thoughts/shared/prs/{number}_description.md` already exists
• If it exists, read it and inform the user you'll be updating it
• Consider what has changed since the last description was written

4. **Gather comprehensive PR information:**

• Get the full PR diff: `gh pr diff {number}`
• If you get an error about no default remote repository, instruct the user to run `gh repo set-default` and select the appropriate repository
• Get commit history: `gh pr view {number} --json commits`
• Review the base branch: `gh pr view {number} --json baseRefName`
• Get PR metadata: `gh pr view {number} --json url,title,number,state`

4b. **Gather reasoning history (if available):**

• Check if reasoning files exist: `ls .git/claude/commits/*/reasoning.md 2>/dev/null`
• If they exist, aggregate them: `bash "$CLAUDE_PROJECT_DIR/.claude/scripts/aggregate-reasoning.sh" main`
• This shows what approaches were tried before the final solution
• Save the output for inclusion in the PR description

5. **Analyze the changes thoroughly:** (ultrathink about the code changes, their architectural implications, and potential impacts)

• Read through the entire diff carefully
• For context, read any files that are referenced but not shown in the diff
• Understand the purpose and impact of each change
• Identify user-facing changes vs internal implementation details
• Look for breaking changes or migration requirements

6. **Handle verification requirements:**

• Look for any checklist items in the "How to verify it" section of the template
• For each verification step:
• If it's a command you can run (like `make check test`, `npm test`, etc.), run it
• If it passes, mark the checkbox as checked: `- [x]`
• If it fails, keep it unchecked and note what failed: `- [ ]` with explanation
• If it requires manual testing (UI interactions, external services), leave unchecked and note for user
• Document any verification steps you couldn't complete

7. **Generate the description:**

• Fill out each section from the template thoroughly:
• Answer each question/section based on your analysis
• Be specific about problems solved and changes made
• Focus on user impact where relevant
• Include technical details in appropriate sections
• Write a concise changelog entry
• **If reasoning files were found (from step 4b):**
• Add an "## Approaches Tried" section before "## How to verify it"
• Include the aggregated reasoning showing failed attempts and what was learned
• This helps reviewers understand the journey, not just the destination
• Ensure all checklist items are addressed (checked or explained)

8. **Save the description:**

• Write the completed description to `thoughts/shared/prs/{number}_description.md`
• Show the user the generated description

9. **Update the PR:**

• Update the PR description directly: `gh pr edit {number} --body-file thoughts/shared/prs/{number}_description.md`
• Confirm the update was successful
• If any verification steps remain unchecked, remind the user to complete them before merging

Important notes:

• This command works across different repositories - always read the local template
• Be thorough but concise - descriptions should be scannable
• Focus on the "why" as much as the "what"
• Include any breaking changes or migration notes prominently
• If the PR touches multiple components, organize the description accordingly
• Always attempt to run verification commands when possible
• Clearly communicate which verification steps need manual testing