One method: gh pr edit --attach. Never commit proof files to any branch. No proof branches, no releases, no docs/pr-evidence/.

When

• PR changes what the user sees (screens, components, colors, layout, copy, animation): screenshot required. Never open the PR without it
• Changed existing UI: add before and after
• Motion (animation, transition, gesture, scroll): add video too
• Capture on iOS and Android, see run-app skill

Steps

1. Save files outside the repo, for example /tmp/<pr>/. Use unique file names per PR.
2. Video: speed and size per test-pr video rules.
3. Upload. Alt text follows #. Up to 50 files per command:

gh pr edit <n> --attach '/tmp/<pr>/before.png#Before: <state>' --attach '/tmp/<pr>/after.png#After: <state>'

4. Read URLs back. --attach appends them at the end of the body:

gh pr view <n> --json body --jq .body | grep -oE 'https://github.com/user-attachments/assets/[a-z0-9-]+'

5. Move URLs into the Evidence section of the pr skill template. Delete the appended copies. Images: HTML table, width=260:

<table>
  <tr><th>Before</th><th>After</th></tr>
  <tr>
    <td><img src="https://github.com/user-attachments/assets/<id>" width="260" alt="Before: <state>" /></td>
    <td><img src="https://github.com/user-attachments/assets/<id>" width="260" alt="After: <state>" /></td>
  </tr>
</table>

Videos: bare URL in table cell, see test-pr video rules.

6. Write body back: gh pr edit <n> --body-file /tmp/<pr>/body.md
7. Check done: step 4 command prints one URL per uploaded file.

Rules

• Done only when PR body contains user-attachments URLs. Never report proof done without step 7 output.
• gh exits non-zero when one upload fails. Body keeps the uploads that worked. Retry only the failed file.
• --body or --body-file replaces the whole body. Always start from step 4 body, never from an old local draft.
• Non-visual PR: command output is proof. No device build unless asked.