gstack/ship/sections/capy-pr.md

Step 19-C: Capy PR body (What changed, Why, Blast radius, Approvals)

Read only when Step 19 printed CAPY_PR: on. Under Capy a person decides the merge from the PR and the READY report, through a Captain, so the body shows what changed in pictures, why, and who approved what. Guide: captain.md beside the Capy gstack skill's SKILL.md.

Order. The gstack-ship-receipt block stays first when Step 19 writes one. Then ## What changed, ## Why, ## Blast radius and ## Approvals, then the standard sections below. Keep ## Summary to commit themes; do not repeat the captions.

1. Pick the evidence: one to three before/after pairs, highest-signal first. The first is the key image.
   • UI change: screenshot the changed screen at the base and on this branch with the browse flow, or your host's browser, at the same size.
   • Skill or prompt change: ~/.claude/skills/gstack/bin/gstack-pr-shots --path <template or SKILL.md> --heading "<changed section>" --caption "<what changed and why>".
   • CLI change: save the output of a command this ship already runs, at the base and on this branch, to files inside the repository (.gstack/tmp/before.txt, .gstack/tmp/after.txt), then ~/.claude/skills/gstack/bin/gstack-pr-shots --before <file> --after <file> --kind terminal --caption "<…>". Never run a command with side effects just to make a picture.
   • No visible surface: picture the source section or test output that best shows the change. gstack-pr-shots refuses inputs that match the secret scanner (PR_SHOTS_INPUT_REFUSED). Remove the secret from the capture; never work around the refusal.
2. Read SHOT_PNG:. A path: use it. unavailable (…): screenshot the printed shot.html with your own browser at 880 px wide and use that PNG. failed (…): use the text version only.
3. Upload. Only for a public repository (gh repo view --json visibility -q .visibility prints PUBLIC). A private repository gets the text version, unless the person approved images for it (record that with gstack-approvals add). Upload each PNG with Capy's PR asset tool (tools.pr.uploadAsset). Embed exactly the URL it returns, with the caption as alt text: ![<caption>](<url>) (a returned bare video URL stays on its own line). If an upload fails, retry once, and only for a transient error. Otherwise use the text version and write image upload failed: <reason> under the caption. Never block publication on an image.
4. Under every image: a one-line caption saying what changed and why, then the contents of the printed text.md (a collapsed text before/after, for readers who cannot see the image and for search).
5. ## Why: two or three sentences. The first states the problem in the person's words (the issue, the failed run, or their request, quoted); the rest say what changes for them. No inventory: BAD "Adds a lint and a CI step." GOOD "'The review loop is too overzealous.' Pass 2 now reads only pass 1's range."
6. ## Blast radius: the body template's item, written once, here: what else the change touches and the one fact that makes that safe, with the evidence-ladder rung it reached (the /investigate skill's Blast radius section, when present).
7. ## Approvals: the output of ~/.claude/skills/gstack/bin/gstack-approvals render, verbatim. It escapes its cells, and the receipt never reads it as an approval citation. A public repo (or unknown visibility) gets only Approved: yes|no (record <id>); never pass --full for a PR body. On APPROVAL_RECORD_UNAVAILABLE keep its text and say so in the READY report. Never type rows by hand.
8. READY report: attach the key image's PNG to the report you send (Capy's message attachments) and give its uploaded URL, so the Captain can show it inline.