feat(agent): let an agent sleep on it

apps/web/src/components/agents/Dream.tsx

@@ -0,0 +1,120 @@
+import { Moon } from "lucide-react";
+import { useCallback, useState } from "react";
+
+import { useI18n } from "../../i18n/context";
+import { useEngine } from "../../lib/engine-context";
+import { useErrorText } from "../../lib/errors";
+import { readJson } from "../../lib/errors";
+import { url } from "../../lib/library";
+import { useLoad } from "../../lib/use-load";
+import { Button } from "../ui";
+
+interface State {
+  dream: boolean;
+  hour: number;
+  last: {
+    day: string;
+    agents: { agent: string; before: number; after: number; refused?: string }[];
+  } | null;
+}
+
+/**
+ * Let the agents sleep on it.
+ *
+ * Memory only ever grew: the same fact written three ways, a correction sitting above the thing it
+ * corrected, a note about a project that finished in March — all of it in every prompt, forever.
+ * Once a night the agent re-reads what it knows and writes back a shorter version that says the
+ * same things.
+ *
+ * Off unless asked, because it is a language-model call per agent per day, and it says what it did:
+ * how many lines went in, how many came out, or why the night was thrown away. The previous memory
+ * is kept in `DREAMS.md` beside the agent, so a bad night is one file to open and one block to
+ * paste back.
+ */
+export function DreamPanel() {
+  const { handshake } = useEngine();
+  const { t } = useI18n();
+  const say = useErrorText();
+  const [busy, setBusy] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  const state = useLoad(
+    useCallback(
+      async () => readJson<State>(await fetch(url(handshake, "/agent/dream"))),
+      [handshake],
+    ),
+    [handshake],
+  );
+
+  const send = async (body: Record<string, unknown>) => {
+    setBusy(true);
+    setError(null);
+    try {
+      await readJson(
+        await fetch(url(handshake, "/agent/dream"), {
+          method: "POST",
+          headers: { "content-type": "application/json" },
+          body: JSON.stringify(body),
+        }),
+      );
+      state.reload();
+    } catch (e) {
+      setError(say(e));
+    } finally {
+      setBusy(false);
+    }
+  };
+
+  const on = state.data?.dream ?? false;
+  const last = state.data?.last ?? null;
+
+  return (
+    <section
+      className="border-line bg-bg-soft mt-6 rounded-[var(--radius-panel)] border p-4"
+      data-testid="dream"
+    >
+      <div className="flex flex-wrap items-center gap-2">
+        <Moon className="text-ai size-4 shrink-0" aria-hidden="true" />
+        <h2 className="flex-1 text-sm font-semibold">{t("agents.dream")}</h2>
+        <label className="text-meta flex items-center gap-1.5">
+          <input
+            type="checkbox"
+            checked={on}
+            disabled={busy}
+            onChange={(e) => void send({ dream: e.target.checked })}
+            className="accent-[var(--color-accent)]"
+          />
+          {t("agents.dream_nightly", { hour: String(state.data?.hour ?? 3) })}
+        </label>
+        <Button variant="ghost" size="sm" disabled={busy} onClick={() => void send({ now: true })}>
+          {busy ? t("agents.dream_working") : t("agents.dream_now")}
+        </Button>
+      </div>
+      <p className="text-fg-faint text-micro mt-1">{t("agents.dream_hint")}</p>
+
+      {error && (
+        <p role="alert" className="text-danger mt-2 text-sm">
+          {error}
+        </p>
+      )}
+
+      {last && (
+        <ul className="text-meta mt-3 space-y-1" data-testid="dream-last">
+          {last.agents.map((one) => (
+            <li key={one.agent} className="text-fg-dim">
+              <span className="font-medium">{one.agent}</span>
+              {" — "}
+              {one.refused
+                ? t("agents.dream_refused", { why: one.refused })
+                : t("agents.dream_shrank", {
+                    before: String(one.before),
+                    after: String(one.after),
+                  })}
+            </li>
+          ))}
+          {last.agents.length === 0 && <li className="text-fg-faint">{t("agents.dream_none")}</li>}
+        </ul>
+      )}
+    </section>
+  );
+}

apps/web/src/i18n/en.json

@@ -519,7 +519,15 @@
     "task_count_one": "{count} open task",
     "task_count_other": "{count} open tasks",
     "dangling": "{from} can hand work to “{to}”, but no agent by that name exists.",
-    "unreadable": "Could not read {path}: {reason}"
+    "unreadable": "Could not read {path}: {reason}",
+    "dream": "Sleep on it",
+    "dream_nightly": "Every night, after {hour}:00",
+    "dream_now": "Do it now",
+    "dream_working": "Thinking…",
+    "dream_hint": "The agent re-reads its own memory and writes it shorter: merge duplicates, keep the latest correction, drop what is finished. It adds nothing. The old version stays in DREAMS.md.",
+    "dream_refused": "skipped — {why}",
+    "dream_shrank": "{before} → {after} lines",
+    "dream_none": "No night yet."
   },
   "finder": {
     "title": "Find",

apps/web/src/i18n/ja.json

@@ -519,7 +519,15 @@
     "task_count_one": "未完了{count}件",
     "task_count_other": "未完了{count}件",
     "dangling": "{from}は「{to}」に仕事を渡せますが、その名前のエージェントは存在しません。",
-    "unreadable": "{path}を読めませんでした：{reason}"
+    "unreadable": "{path}を読めませんでした：{reason}",
+    "dream": "寝かせて整理",
+    "dream_nightly": "毎晩 {hour} 時以降",
+    "dream_now": "今すぐ整理",
+    "dream_working": "整理中…",
+    "dream_hint": "エージェントが自分の記憶を読み直して短くします：重複をまとめ、最新の訂正を残し、終わったことを落とす。新しいことは足しません。元の版は DREAMS.md に残ります。",
+    "dream_refused": "見送り — {why}",
+    "dream_shrank": "{before} → {after} 行",
+    "dream_none": "まだ一度もありません。"
   },
   "finder": {
     "title": "絞り込み",

apps/web/src/i18n/vi.json

@@ -519,7 +519,15 @@
     "task_count_one": "{count} việc treo",
     "task_count_other": "{count} việc treo",
     "dangling": "{from} có thể giao việc cho “{to}”, nhưng không có agent nào tên đó.",
-    "unreadable": "Không đọc được {path}: {reason}"
+    "unreadable": "Không đọc được {path}: {reason}",
+    "dream": "Ngủ & ôn lại",
+    "dream_nightly": "Mỗi đêm, sau {hour} giờ",
+    "dream_now": "Ôn ngay",
+    "dream_working": "Đang ôn…",
+    "dream_hint": "Agent đọc lại trí nhớ của nó rồi viết gọn: gộp trùng, giữ bản sửa mới nhất, bỏ việc đã xong. Không thêm điều gì mới. Bản cũ vẫn nằm trong DREAMS.md.",
+    "dream_refused": "bỏ qua — {why}",
+    "dream_shrank": "{before} → {after} dòng",
+    "dream_none": "Chưa ôn lần nào."
   },
   "finder": {
     "title": "Tìm",

apps/web/src/i18n/zh.json

@@ -519,7 +519,15 @@
     "task_count_one": "{count}项未完成",
     "task_count_other": "{count}项未完成",
     "dangling": "{from}可以把活交给“{to}”，但没有叫这个名字的智能体。",
-    "unreadable": "读不了{path}：{reason}"
+    "unreadable": "读不了{path}：{reason}",
+    "dream": "睡一觉再整理",
+    "dream_nightly": "每晚 {hour} 点后",
+    "dream_now": "立即整理",
+    "dream_working": "整理中…",
+    "dream_hint": "助理重读自己的记忆并写得更短：合并重复、保留最新的更正、去掉已完成的。不会新增任何内容。旧版本保留在 DREAMS.md。",
+    "dream_refused": "跳过 — {why}",
+    "dream_shrank": "{before} → {after} 行",
+    "dream_none": "还没有整理过。"
   },
   "finder": {
     "title": "筛选",

apps/web/src/screens/AgentsScreen.tsx

@@ -1,3 +1,4 @@
+import { DreamPanel } from "../components/agents/Dream";
 import { AnimatePresence, motion } from "motion/react";
 import { useCallback, useMemo, useRef, useState } from "react";
 
@@ -151,6 +152,7 @@ export function AgentsScreen() {
   return (
     <Page title={t("agents.title")} subtitle={t("agents.subtitle")}>
       <PageGlow />
+      <DreamPanel />
 
       {error && (
         <p className="border-rec/30 bg-rec-soft text-rec text-meta rounded-lg border px-3 py-2">

crates/summo-agent/src/memory.rs

@@ -124,6 +124,26 @@ pub fn remember(path: &Path, today: &str, text: &str) -> Result<bool> {
     Ok(true)
 }
 
+/// Replace the whole list, keeping the file's shape.
+///
+/// For consolidation — see `summo_engine::dream`, the one caller. Deliberately not exposed as a
+/// tool: an agent that could rewrite its own memory wholesale mid-run could erase a correction it
+/// had just been given, and the value of memory is that the user can rely on what they put in it.
+/// A night's consolidation is a different act, and it archives what it replaces before it writes.
+pub fn replace(path: &Path, facts: &[String], today: &str) -> Result<()> {
+    let mut out = String::from("# Memory\n\n");
+    for text in facts.iter().take(MAX_LINES) {
+        let text = text.trim();
+        if !text.is_empty() {
+            out.push_str(&format!("- {today} — {text}\n"));
+        }
+    }
+    if let Some(parent) = path.parent() {
+        std::fs::create_dir_all(parent).map_err(|e| Error::io(parent, e))?;
+    }
+    std::fs::write(path, out).map_err(|e| Error::io(path, e))
+}
+
 /// Forget one fact, by exact text. What makes the memory the user's rather than the agent's.
 pub fn forget(path: &Path, text: &str) -> Result<bool> {
     let facts = load(path);

crates/summo-core/src/settings.rs

@@ -25,11 +25,26 @@ pub struct Settings {
     pub llm: Llm,
     pub storage: Storage,
     pub interface: Interface,
+    pub agents: Agents,
     /// Fields this build does not know about, kept so a downgrade does not erase them.
     #[serde(flatten)]
     pub unknown: BTreeMap<String, serde_json::Value>,
 }
 
+/// What the agents do when nobody is asking.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(default)]
+pub struct Agents {
+    /// Once a day, let each agent re-read and shorten its own memory.
+    ///
+    /// Off by default. It costs a language-model call per agent per day, and on the first day
+    /// there is nothing to consolidate — a memory of four lines is already as short as it gets.
+    pub dream: bool,
+    /// Hour, local, after which it may happen. Late, because it is unattended work on a file that
+    /// steers every later answer, and the user should be asleep rather than mid-sentence.
+    pub dream_hour: u8,
+}
+
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 #[serde(default)]
 pub struct Recording {
@@ -168,6 +183,15 @@ pub struct Interface {
     pub show_performance: bool,
 }
 
+impl Default for Agents {
+    fn default() -> Self {
+        Self {
+            dream: false,
+            dream_hour: 3,
+        }
+    }
+}
+
 impl Default for Settings {
     fn default() -> Self {
         Self {
@@ -177,6 +201,7 @@ impl Default for Settings {
             llm: Llm::default(),
             storage: Storage::default(),
             interface: Interface::default(),
+            agents: Agents::default(),
             unknown: BTreeMap::new(),
         }
     }