diff --git a/prompt.md b/prompt.md
index b03df2c..25de243 100644
--- a/prompt.md
+++ b/prompt.md
@@ -25,6 +25,13 @@ fixes exactly when it is not `Yes`, and Minor issues alone never block. For UI
 changes, check that the result is aligned, clean, and pixel-perfect, and that
 included screenshots prove the intended result was achieved.
 
+The review must read at a glance: everything outside `<details>` blocks totals
+under 512 bytes. Keep only the assessment line, the section headings, and a
+one-line `@bot` instruction visible. Put each strength, each issue, and each
+recommendation in its own top-level `<details>` block, never inside a list item,
+with a `<summary>` of the `file:line` and a few words and the what, why, and how
+inside. The template's `**Reasoning:**` goes in a `<details>` block too.
+
 For an `issue_comment` or `pull_request_review_comment` event, treat the `body`
 in the triggering comment payload below as the user's exact instruction.
 
diff --git a/run.ts b/run.ts
index 8978dde..98aea80 100644
--- a/run.ts
+++ b/run.ts
@@ -52,6 +52,16 @@ async function postComment(body: string): Promise<void> {
   });
 }
 
+// A review must read at a glance: when the agent left more than VISIBLE_BYTES
+// outside <details> blocks, the whole review folds under its verdict line.
+const VISIBLE_BYTES = 512;
+function fold(body: string): string {
+  const visible = body.replace(/<details>[\s\S]*?<\/details>/g, "");
+  if (new TextEncoder().encode(visible).length <= VISIBLE_BYTES) return body;
+  const verdict = body.match(/\*\*Ready to merge\?\*\*.*/)?.[0] ?? "Review";
+  return `${verdict}\n\n<details>\n<summary>Details</summary>\n\n${body}\n\n</details>`;
+}
+
 // A pull request event is a review request, so the response becomes a review:
 // changes are requested when the agent asked @bot to fix something, a failed
 // run only comments, and anything else approves.
@@ -63,7 +73,7 @@ async function postResult(body: string): Promise<void> {
     ? "COMMENT"
     : "APPROVED";
   await gitea(REVIEWER_TOKEN, `repos/${REPO}/pulls/${INDEX}/reviews`, {
-    body: stripAnsi(body),
+    body: fold(stripAnsi(body)),
     event,
   });
 }