diff --git a/src/workspaces/officerdev/src/apps/Chat/EmbeddableChat/prompt-recall.test.ts b/src/workspaces/officerdev/src/apps/Chat/EmbeddableChat/prompt-recall.test.ts
new file mode 100644
index 00000000..69bbad15
--- /dev/null
+++ b/src/workspaces/officerdev/src/apps/Chat/EmbeddableChat/prompt-recall.test.ts
@@ -0,0 +1,37 @@
+import { describe, expect, it } from 'bun:test';
+
+/*
+  The rule, as a pure function, because the interesting part is not the DOM.
+
+  History must never clobber text the person typed, and must still be walkable once a recalled prompt is
+  sitting in the box. Those two pull in opposite directions and the second is what a naive "only when empty"
+  check breaks.
+*/
+const mayRecall = (value: string, recalling: boolean): boolean => value.trim() === '' || recalling;
+
+describe('when history may take the arrow key', () => {
+  it('takes it on an empty composer', () => {
+    expect(mayRecall('', false)).toBe(true);
+  });
+
+  // The bug this rule exists for: the caret is on the first line of a one-line draft, so every position
+  // test passes, and Up used to replace what you were writing.
+  it('leaves a draft alone', () => {
+    expect(mayRecall('half a thought', false)).toBe(false);
+  });
+
+  // Without this, you could step back exactly once and then be refused, because the recalled prompt is
+  // itself text in the box.
+  it('keeps walking once it is in the history', () => {
+    expect(mayRecall('a prompt from earlier', true)).toBe(true);
+  });
+
+  it('treats whitespace as empty', () => {
+    expect(mayRecall('   ', false)).toBe(true);
+    expect(mayRecall('\n\t ', false)).toBe(true);
+  });
+
+  it('protects a draft that merely starts with whitespace', () => {
+    expect(mayRecall('  still typing', false)).toBe(false);
+  });
+});
diff --git a/src/workspaces/officerdev/src/apps/Chat/EmbeddableChat/useEmbeddableChat.ts b/src/workspaces/officerdev/src/apps/Chat/EmbeddableChat/useEmbeddableChat.ts
index 012feec5..5420fc92 100644
--- a/src/workspaces/officerdev/src/apps/Chat/EmbeddableChat/useEmbeddableChat.ts
+++ b/src/workspaces/officerdev/src/apps/Chat/EmbeddableChat/useEmbeddableChat.ts
@@ -389,15 +389,26 @@ export function useEmbeddableChat(params: UseEmbeddableChatParams, onMessageComp
   /**
    * Recall a previous prompt, the way a shell does.
    *
-   * Up only reaches the history from the FIRST line and Down only from the last, so in a multi-line draft
-   * the arrows still move the caret — there is a line above to go to, and taking the key would strand the
-   * cursor. On the first line there is nowhere up to go, which is exactly when history is what you meant.
-   * `step` returning null (empty history, or already at the oldest) leaves the key alone too.
+   * **Only from an empty composer.** The caret-on-the-first-line test below is not enough on its own, and
+   * that was the bug: with a one-line draft you were typing, the caret IS on the first line, so Up replaced
+   * what you had written with something from last week. A draft is not recoverable from anywhere, and
+   * history is — so the tie goes to the draft, always.
+   *
+   * `isRecalling` is what keeps the rule from making the feature useless. Once a recalled prompt is in the
+   * box the box is not empty, so a plain emptiness test would allow one step back and then refuse; walking
+   * further is still allowed because that text came from the history rather than from you.
+   *
+   * Whitespace counts as empty. A composer holding two spaces is not a draft anybody would miss, and an
+   * invisible character silently blocking Up is worse than losing it.
+   *
+   * The line tests stay on top of that: in a recalled prompt spanning three lines, Up from the middle moves
+   * the caret, because there is a line above to go to and taking the key would strand the cursor.
    */
   const recallPrompt = (ev: KeyboardEvent<HTMLTextAreaElement>, direction: -1 | 1): void => {
     const field = ev.currentTarget;
     const { selectionStart, selectionEnd, value } = field;
     if (selectionStart !== selectionEnd) return; // a selection means the arrows are extending/collapsing it
+    if (value.trim() !== '' && !history.isRecalling()) return;
     const onEdge =
       direction === -1 ? !value.slice(0, selectionStart).includes('\n') : !value.slice(selectionEnd).includes('\n');
     if (!onEdge) return;
diff --git a/src/workspaces/officerdev/src/apps/Chat/EmbeddableChat/usePromptHistory.ts b/src/workspaces/officerdev/src/apps/Chat/EmbeddableChat/usePromptHistory.ts
index 2daeeb55..2c0d1acc 100644
--- a/src/workspaces/officerdev/src/apps/Chat/EmbeddableChat/usePromptHistory.ts
+++ b/src/workspaces/officerdev/src/apps/Chat/EmbeddableChat/usePromptHistory.ts
@@ -25,6 +25,15 @@ export type PromptHistory = {
    * whatever it normally does.
    */
   step: (direction: -1 | 1, current: string) => string | null;
+  /**
+   * Are we currently walking the history, rather than composing?
+   *
+   * The caller needs this to answer "may Up take this key" without also making the history unusable. The
+   * rule is that history must never clobber text the PERSON typed — but once a recalled prompt is in the
+   * box, the box is not empty any more, and a plain emptiness test would allow exactly one step back and
+   * then refuse. This is the difference between "there is text" and "there is text of yours".
+   */
+  isRecalling: () => boolean;
 };
 
 export function usePromptHistory(): PromptHistory {
@@ -87,5 +96,7 @@ export function usePromptHistory(): PromptHistory {
     return list[at - 1] ?? null;
   }, []);
 
-  return { record, step };
+  const isRecalling = useCallback(() => indexRef.current !== null, []);
+
+  return { record, step, isRecalling };
 }