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name: pr-walkthrough description: Build a human-facing reading guide for a GitHub pull request (where to start, what each file changes, what it impacts) using the reviewer PR session + code graph. Use when the user asks to walk a human reviewer through a PR ("PR walkthrough", "гид по PR", "как читать этот PR", "проведи по PR"). NOT a bug review (see review-pr). Requires the reviewer MCP server + base index.

PR walkthrough (reading guide for a human reviewer)

Help a human reviewer orient in a PR — not find bugs. Produce a markdown guide: where to start (by centrality), what each file changes, and what it impacts ("careful, affects X"). Separate from bug findings (review-pr).

Always answer the user in Russian (the project language). Tool calls, identifiers and path:line stay verbatim.

Tools

Plus the PR-session tools (reviewer MCP): prepare_review, get_impact, get_changed_file_diff, find_callers, get_related_symbols, read_file; optional get_subsystem_summaries (PRI-159); optional post_pr_walkthrough (only on explicit user request).

Pipeline

1. Resolve repo & prepare the session. Resolve repo (git remote). Call prepare_review(repo, pr). If it returns {"status": "skipped"} (branch not in REVIEW_BRANCHES), tell the user (in Russian) and stop.

2. Reading order (centrality). Call get_impact(repo, pr) → changed symbols and their callers. Order "start here" by how much depends on each changed symbol (most central first). Graph down → fall back to ordering by file (fail-open).

3. What each file changes. For each changed file, get_changed_file_diff(repo, pr, path) → one line describing what it changes.

4. Impact ("careful, affects X"). For the central changed symbols, find_callers / get_related_symbols → who depends on them. Every "affects X" must be backed by a real caller.

5. Subsystem prior (optional). get_subsystem_summaries(repo, pr.base_ref, query="<PR title + changed file paths>") → name the touched subsystem(s) in one line. Pass the PR's target branch pr.base_ref (from the prepare_review response), NOT the local git branch — subsystem summaries are indexed per target branch (base:<branch>). Empty / unavailable → skip (fail-open).

6. Assemble the guide (Russian markdown):

   • Начни отсюда — ordered list (most central first).
   • По файлам — one line per changed file.
   • Осторожно, влияет на — impacted symbols + their callers.
   • (optional) Подсистемы — 1–2 lines from summaries.

7. Output. Print the guide to the user by default. Post to the PR ONLY on explicit user request: confirm first, then call post_pr_walkthrough(repo, pr, markdown) (posts a PR review comment with a <!-- ai-walkthrough --> marker, separate from bug findings).

Grounding (hard rule)

Every "affects X" is backed by a real find_callers result. Never invent callers or impact.

Notes

• This is a reading guide, NOT a bug review — no findings, no inline severity comments.
• Posting to the PR is outward-facing and never happens without explicit user request + confirmation.
• Works without PRI-159 summaries and degrades gracefully when the graph is unavailable.