Answer budget within the context window; enforced reviews of completed todos

Context window
- Requests asked for the model's full max_output, but providers count
  input + output against the window: long chats with large-output models
  (DeepSeek V4.1 Flash, 384k) failed with "input too long" before automatic
  compaction (85 %) kicked in. max_tokens is now what the window leaves
  (estimated input = last usage + messages since), the chat is compacted when
  less than 32k would remain for an answer, and a context-overflow error
  compacts and retries once.
- ModelConfig.max_input (catalogue limit.input, editable in the provider
  settings) lowers the compaction threshold for models with an input limit.

Enforced reviews (modes with refine.rounds > 0, refine.after_todos default on)
- Every todo marked completed is reviewed against the work since the last
  review; with findings it is reopened and the feedback goes to the agent
  (max. rounds per todo). Passed reviews leave a visible note.
- Ending the turn with open todos sends the agent back to work while it makes
  progress (max. 10 reminders in a row without progress); such modes may take
  up to 2,000 steps per turn. Reaching the step limit is reported.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/src/components/ChatView.tsx

@@ -115,7 +115,36 @@ function BackgroundResult({ text }: { text: string }) {
   );
 }
 
-const REFINE_RE = /^<refine-feedback round="([^"]*)" reviewer="([^"]*)">\n?([\s\S]*?)\n?<\/refine-feedback>/;
+const REFINE_RE = /^<refine-feedback round="([^"]*)" reviewer="([^"]*)"(?: todos="\d+")?>\n?([\s\S]*?)\n?<\/refine-feedback>/;
+/** Enforced reviews: a completed todo passed, or a reminder about open todos. */
+const NOTE_RE = /^<(refine-approved|todo-reminder)(?: reviewer="([^"]*)")?(?: open="\d+")?>\n?([\s\S]*?)\n?<\/(?:refine-approved|todo-reminder)>/;
+/** Messages from the harness shown as cards instead of user bubbles. */
+const isHarnessNote = (text: string) => BG_RE.test(text) || REFINE_RE.test(text) || NOTE_RE.test(text);
+
+/** A todo passed its review, or the agent was sent back to its open todos. */
+function HarnessNote({ text }: { text: string }) {
+  const t = useT();
+  const m = text.match(NOTE_RE);
+  if (!m) return null;
+  const [, kind, reviewer, body] = m;
+  const items = body.split("\n").map((l) => l.replace(/^- /, "").trim()).filter(Boolean);
+  const approved = kind === "refine-approved";
+  return (
+    <div className={`harness-note ${approved ? "ok" : ""}`}>
+      <Icon name={approved ? "check" : "refresh"} />
+      <span className="grow">
+        <b>{t(approved ? "chat.reviewPassed" : "chat.todoReminder", { n: items.length })}</b> {items.join(" · ")}
+      </span>
+      {reviewer && <span className="chip">{reviewer}</span>}
+    </div>
+  );
+}
+
+function HarnessMessage({ text }: { text: string }) {
+  if (REFINE_RE.test(text)) return <RefineFeedback text={text} />;
+  if (NOTE_RE.test(text)) return <HarnessNote text={text} />;
+  return <BackgroundResult text={text} />;
+}
 
 /** Findings of the review loop, sent back to the agent. */
 function RefineFeedback({ text }: { text: string }) {
@@ -469,14 +498,14 @@ export function ChatView({ sessionId, onMenu, onClosePane }: { sessionId: string
               );
             }
             const allTexts = m.parts.filter((p) => p.type === "text") as { text: string }[];
-            const background = allTexts.filter((p) => BG_RE.test(p.text) || REFINE_RE.test(p.text));
-            const texts = allTexts.filter((p) => !BG_RE.test(p.text) && !REFINE_RE.test(p.text));
+            const background = allTexts.filter((p) => isHarnessNote(p.text));
+            const texts = allTexts.filter((p) => !isHarnessNote(p.text));
             const imgs = m.parts.filter((p) => p.type === "image") as { image: ImageData }[];
             if (texts.length === 0 && imgs.length === 0) {
               return background.length ? (
                 <div key={m.id} className="msg">
                   {background.map((p, i) => (
-                    REFINE_RE.test(p.text) ? <RefineFeedback key={i} text={p.text} /> : <BackgroundResult key={i} text={p.text} />
+                    <HarnessMessage key={i} text={p.text} />
                   ))}
                 </div>
               ) : null;
@@ -484,7 +513,7 @@ export function ChatView({ sessionId, onMenu, onClosePane }: { sessionId: string
             return (
               <div key={m.id} className="msg">
                 {background.map((p, i) => (
-                  REFINE_RE.test(p.text) ? <RefineFeedback key={i} text={p.text} /> : <BackgroundResult key={i} text={p.text} />
+                  <HarnessMessage key={i} text={p.text} />
                 ))}
                 <div className="msg-user">
                   {!busy && !readOnly && (