---
name: walk-pr
description: 'Walk through a PR or large diff together — your own or someone else''s — one sub-changeset at a time and one review topic at a time within it. Verbatim quotes from both sides, section-by-section mapping of what survived / cut / moved, honest trade-offs with a recommended call. At the end, present a plan of the comments captured during the walk; on approval, post them as a PR review. Optional --canvas runs the walk in a live HTML artifact that replaces chat as the review surface. Use when reviewing a substantive PR collaboratively or walking a large refactor. Triggers: walk pr, walk diff, walk me through, pr walkthrough, review collaboratively, review this change with me.'
user-invocable: true
---

Walk the user through a PR or large diff **one sub-changeset at a time** — a group of files that makes sense together — and **one review topic at a time within it**. **Assume the user is reviewing cold** — no prior context on the touched code, so the walk has to surface what's needed. Open with a categorized overview (load-bearing changes vs copies / data, recommended order biggest-signal-first); skip on trivial diffs. For each sub-changeset: first ground the user in what the touched code is and does (just enough to read the diff), then show verbatim quotes from both sides — never paraphrased — map section-by-section what survived / cut / moved with each cut justified, report net change. Then surface review topics (probes, trade-offs, recommendations) **one at a time**: state the topic, recommend a call, wait for the user's response, only then advance. Don't batch — "thoughts on all of these?" is the cognitive-load failure mode this skill is built to prevent. Hold positions under pushback when evidence still supports them.

**Post at end.** Capture the user's response per topic. When the walk completes, present a plan of the captured comments — line-anchored where the topic ties to a specific code location, file-level or PR-level otherwise — via `ExitPlanMode`. On approval, post them as a single PR review using available GitHub tools (`gh pr review` / `mcp__github__pull_request_review_write` / API). Whether and how the PR's author addresses the comments is the manifest workflow's job downstream, not /walk-pr's.

**`--canvas`.** Load `references/CANVAS_MODE.md`. The HTML artifact **replaces** chat as the walkthrough surface — verbatim quotes, mappings, trade-offs, probes, and per-topic comment textareas all live in the canvas, generated once upfront. The user navigates self-paced and clicks a single end-of-walk **Copy as prompt** button to hand the consolidated review result back to chat. **Input** = PR number, PR URL, diff range, or nothing (infer the current branch's PR; fall back to `origin/main..HEAD`).