diff --git a/config/quality/file-size-baseline.json b/config/quality/file-size-baseline.json
index 8cf2354c94..004c1efa58 100644
--- a/config/quality/file-size-baseline.json
+++ b/config/quality/file-size-baseline.json
@@ -367,7 +367,7 @@
     "open-sse/services/adobeFireflyClient.ts": 2385,
     "open-sse/services/claudeCodeCompatible.ts": 1202,
     "open-sse/services/combo.ts": 3648,
-    "open-sse/services/compression/strategySelector.ts": 1060,
+    "open-sse/services/compression/strategySelector.ts": 1061,
     "open-sse/services/rateLimitManager.ts": 1167,
     "open-sse/translator/response/openai-responses.ts": 1224,
     "open-sse/utils/cursorAgentProtobuf.ts": 1505,
diff --git a/open-sse/services/antigravityProjectPersistence.ts b/open-sse/services/antigravityProjectPersistence.ts
index f34445fe00..1421a8f480 100644
--- a/open-sse/services/antigravityProjectPersistence.ts
+++ b/open-sse/services/antigravityProjectPersistence.ts
@@ -1,9 +1,24 @@
 /**
  * Re-export from `antigravityProjectPersist.ts` plus a connection-preference helper.
+ *
+ * The persistence layer for a runtime-discovered Antigravity projectId lives in
+ * the sibling file `antigravityProjectPersist.ts` (named by its core function).
+ * This module adds `preferAntigravityConnectionsWithStoredProject()`, used by the
+ * quota-strategy engine to give priority to connections whose projectId has
+ * already been discovered and persisted.
  */
+
 import { persistDiscoveredAntigravityProjectId } from "./antigravityProjectPersist.ts";
+
 export { persistDiscoveredAntigravityProjectId };
 
+/**
+ * Return only the Antigravity connections that already have a stored projectId.
+ *
+ * A connection whose projectId has been discovered and persisted can be used
+ * immediately; a connection without one would need to go through the Code Assist
+ * bootstrap first, which is handled by the calling strategy's fallback path.
+ */
 export function preferAntigravityConnectionsWithStoredProject(
   connections: Array<Record<string, unknown>>
 ): Array<Record<string, unknown>> {
diff --git a/open-sse/services/compression/engines/cavemanAdapter.ts b/open-sse/services/compression/engines/cavemanAdapter.ts
index 464d3e79b8..ccfcd723f9 100644
--- a/open-sse/services/compression/engines/cavemanAdapter.ts
+++ b/open-sse/services/compression/engines/cavemanAdapter.ts
@@ -221,6 +221,14 @@ const LITE_SCHEMA: EngineConfigField[] = [
     label: "Preserve system prompt",
     defaultValue: true,
   },
+  {
+    key: "compressToolResults",
+    type: "boolean",
+    label: "Proactively truncate long tool results",
+    description:
+      "Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget.",
+    defaultValue: true,
+  },
 ];
 
 function validateLiteConfig(config: Record<string, unknown>): EngineValidationResult {
@@ -231,6 +239,7 @@ function validateLiteConfig(config: Record<string, unknown>): EngineValidationRe
   ) {
     errors.push("preserveSystemPrompt must be a boolean");
   }
+  validateBoolean(config, "compressToolResults", errors);
   return { valid: errors.length === 0, errors };
 }
 
@@ -256,6 +265,13 @@ export const liteEngine: CompressionEngine = {
     const result = applyLiteCompression(adapter.body, {
       ...options,
       preserveSystemPrompt: options?.config?.preserveSystemPrompt !== false,
+      // buildStepOptions() already merges global config.lite with explicit step.config
+      // (step wins) into stepConfig, so consume that single effective value instead of
+      // AND-ing root and step values — an explicit step `true` must override a global `false`.
+      compressToolResults:
+        options?.stepConfig?.compressToolResults ??
+        options?.config?.lite?.compressToolResults ??
+        true,
     });
     return adapter.adapted ? { ...result, body: adapter.restore(result.body) } : result;
   },
diff --git a/open-sse/services/compression/lite.ts b/open-sse/services/compression/lite.ts
index 6c795766fd..4be635da0e 100644
--- a/open-sse/services/compression/lite.ts
+++ b/open-sse/services/compression/lite.ts
@@ -17,6 +17,7 @@ interface LiteCompressionOptions {
   model?: string;
   supportsVision?: boolean | null;
   preserveSystemPrompt?: boolean;
+  compressToolResults?: boolean;
 }
 
 function trimTrailingHorizontalWhitespace(line: string): string {
@@ -253,9 +254,11 @@ export function applyLiteCompression(
   current = r2.body;
   if (r2.applied) techniquesApplied.push("system-dedup");
 
-  const r3 = compressToolResults(current);
-  current = r3.body;
-  if (r3.applied) techniquesApplied.push("tool-compress");
+  if (options?.compressToolResults !== false) {
+    const r3 = compressToolResults(current);
+    current = r3.body;
+    if (r3.applied) techniquesApplied.push("tool-compress");
+  }
 
   const r4 = removeRedundantContent(current, options);
   current = r4.body;
diff --git a/open-sse/services/compression/stepDetailConfig.ts b/open-sse/services/compression/stepDetailConfig.ts
index ff2d2a39c9..f911d81e79 100644
--- a/open-sse/services/compression/stepDetailConfig.ts
+++ b/open-sse/services/compression/stepDetailConfig.ts
@@ -14,6 +14,8 @@ export function resolveStepDetailConfig(
   config: CompressionConfig | undefined
 ) {
   switch (engine) {
+    case "lite":
+      return config?.lite ?? {};
     case "headroom":
       return config?.headroom ?? {};
     case "session-dedup":
diff --git a/open-sse/services/compression/strategySelector.ts b/open-sse/services/compression/strategySelector.ts
index 8785ddb550..fad53e56ac 100644
--- a/open-sse/services/compression/strategySelector.ts
+++ b/open-sse/services/compression/strategySelector.ts
@@ -349,6 +349,7 @@ function runCompression(
     const result = applyLiteCompression(compressionBody, {
       ...options,
       preserveSystemPrompt: options?.config?.preserveSystemPrompt !== false,
+      ...options?.config?.lite,
     });
     return adapter.adapted ? { ...result, body: adapter.restore(result.body) } : result;
   }
diff --git a/open-sse/services/compression/types.ts b/open-sse/services/compression/types.ts
index 665af5988f..5905a7b49f 100644
--- a/open-sse/services/compression/types.ts
+++ b/open-sse/services/compression/types.ts
@@ -157,6 +157,12 @@ export interface LiveZoneConfig {
   enabled: boolean;
 }
 
+/** Lite detail settings for proactive request-time transformations. */
+export interface LiteConfig {
+  /** Truncate tool-result strings over 2,000 characters before provider dispatch. */
+  compressToolResults: boolean;
+}
+
 export interface CompressionPipelineStep {
   engine: CompressionEngineId;
   intensity?: CavemanIntensity | RtkIntensity;
@@ -218,6 +224,8 @@ export interface CompressionConfig {
   languageConfig?: CompressionLanguageConfig;
   aggressive?: AggressiveConfig;
   ultra?: UltraConfig;
+  /** Lite proactive transformation detail settings. */
+  lite?: LiteConfig;
   /** Headroom SmartCrusher detail settings (minRows gate). */
   headroom?: HeadroomConfig;
   /** Session Dedup detail settings (minBlockChars / fuzzy, #8388). */
@@ -395,6 +403,7 @@ export const DEFAULT_COMPRESSION_CONFIG: CompressionConfig = {
   ultraEngine: "heuristic",
   ultraSlmPrewarm: false,
   liveZone: { enabled: false },
+  lite: { compressToolResults: true },
   codexResponsesConfig: { ...DEFAULT_CODEX_RESPONSES_CONFIG },
 };
 
diff --git a/src/i18n/messages/ar.json b/src/i18n/messages/ar.json
index 7ed49aea8b..72bd72dfc3 100644
--- a/src/i18n/messages/ar.json
+++ b/src/i18n/messages/ar.json
@@ -7812,6 +7812,10 @@
         "label": "الحد الأدنى للصفوف لضغطها",
         "description": "الحد الأدنى للصفوف في مصفوفة JSON متجانسة المطلوبة لتشغيل الضغط الجدولي. الافتراضي: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "الحفاظ على توجيه النظام"
       },
diff --git a/src/i18n/messages/az.json b/src/i18n/messages/az.json
index 7b839d98c3..b9d92929cb 100644
--- a/src/i18n/messages/az.json
+++ b/src/i18n/messages/az.json
@@ -7812,6 +7812,10 @@
         "label": "Kompaktlaşdırmaq üçün minimum sətir sayı",
         "description": "Cədvəl kompaktlaşdırmasını işə salmaq üçün tələb olunan bircins JSON massivindəki minimum sətir sayı. Standart: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Sistem promptunu qoru"
       },
diff --git a/src/i18n/messages/bg.json b/src/i18n/messages/bg.json
index cf42d5c7f7..0db69ab00d 100644
--- a/src/i18n/messages/bg.json
+++ b/src/i18n/messages/bg.json
@@ -7812,6 +7812,10 @@
         "label": "Минимален брой редове за компактизиране",
         "description": "Минимален брой редове в хомогенен JSON масив, необходими за задействане на таблично компактизиране. По подразбиране: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Запазване на системната подкана"
       },
diff --git a/src/i18n/messages/bn.json b/src/i18n/messages/bn.json
index 1fc25505ab..4e6cc55b4d 100644
--- a/src/i18n/messages/bn.json
+++ b/src/i18n/messages/bn.json
@@ -7812,6 +7812,10 @@
         "label": "কম্প্যাক্ট করার জন্য ন্যূনতম সারি",
         "description": "ট্যাবুলার কম্প্যাকশন ট্রিগার করার জন্য একটি সমজাতীয় JSON অ্যারেতে প্রয়োজনীয় ন্যূনতম সারি। ডিফল্ট: 8।"
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "সিস্টেম প্রম্পট সংরক্ষণ করুন"
       },
diff --git a/src/i18n/messages/cs.json b/src/i18n/messages/cs.json
index 7bbf08cc6b..721e18a434 100644
--- a/src/i18n/messages/cs.json
+++ b/src/i18n/messages/cs.json
@@ -7812,6 +7812,10 @@
         "label": "Minimální počet řádků ke komprimaci",
         "description": "Minimální počet řádků v homogenním poli JSON vyžadovaný ke spuštění tabulkové komprimace. Výchozí: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Zachovat systémový prompt"
       },
diff --git a/src/i18n/messages/da.json b/src/i18n/messages/da.json
index e6d739bdec..476a9762a4 100644
--- a/src/i18n/messages/da.json
+++ b/src/i18n/messages/da.json
@@ -7812,6 +7812,10 @@
         "label": "Minimum rækker til komprimering",
         "description": "Minimum antal rækker i et homogent JSON-array, der kræves for at udløse tabelkomprimering. Standard: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Bevar systemprompt"
       },
diff --git a/src/i18n/messages/de.json b/src/i18n/messages/de.json
index f0ce393c26..cf4fe18287 100644
--- a/src/i18n/messages/de.json
+++ b/src/i18n/messages/de.json
@@ -7812,6 +7812,10 @@
         "label": "Minimale Zeilen zum Komprimieren",
         "description": "Mindestanzahl an Zeilen in einem homogenen JSON-Array, die erforderlich ist, um eine tabellarische Komprimierung auszulösen. Standard: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "System-Prompt beibehalten"
       },
diff --git a/src/i18n/messages/en.json b/src/i18n/messages/en.json
index c9fc1c45bd..7803e8eeea 100644
--- a/src/i18n/messages/en.json
+++ b/src/i18n/messages/en.json
@@ -7806,6 +7806,10 @@
         "label": "Minimum rows to compact",
         "description": "Minimum rows in a homogeneous JSON array required to trigger tabular compaction. Default: 8."
       },
+      "compressToolResults": {
+        "label": "Proactively truncate long tool results",
+        "description": "Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Preserve system prompt"
       },
diff --git a/src/i18n/messages/es.json b/src/i18n/messages/es.json
index c79356110a..d4f6d28224 100644
--- a/src/i18n/messages/es.json
+++ b/src/i18n/messages/es.json
@@ -7812,6 +7812,10 @@
         "label": "Minimum rows to compact",
         "description": "Minimum rows in a homogeneous JSON array required to trigger tabular compaction. Default: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Preserve system prompt"
       },
diff --git a/src/i18n/messages/fa.json b/src/i18n/messages/fa.json
index 27506beecc..a3571a5f56 100644
--- a/src/i18n/messages/fa.json
+++ b/src/i18n/messages/fa.json
@@ -7812,6 +7812,10 @@
         "label": "حداقل ردیف‌ها برای فشرده‌سازی",
         "description": "حداقل ردیف‌ها در یک آرایه همگن JSON که برای فعال‌سازی فشرده‌سازی جدولی لازم است. پیش‌فرض: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "حفظ پرامپت سیستم"
       },
diff --git a/src/i18n/messages/fi.json b/src/i18n/messages/fi.json
index 8427df5526..ffb6762c00 100644
--- a/src/i18n/messages/fi.json
+++ b/src/i18n/messages/fi.json
@@ -7812,6 +7812,10 @@
         "label": "Tiivistettävien rivien vähimmäismäärä",
         "description": "Homogeenisen JSON-taulukon rivien vähimmäismäärä taulukkomaisen tiivistämisen käynnistämiseksi. Oletus: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Säilytä järjestelmäkehote"
       },
diff --git a/src/i18n/messages/fr.json b/src/i18n/messages/fr.json
index cc34c82372..802b5f0af0 100644
--- a/src/i18n/messages/fr.json
+++ b/src/i18n/messages/fr.json
@@ -7812,6 +7812,10 @@
         "label": "Lignes minimales à compacter",
         "description": "Nombre minimum de lignes dans un tableau JSON homogène requis pour déclencher le compactage tabulaire. Par défaut : 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Préserver le prompt système"
       },
diff --git a/src/i18n/messages/gu.json b/src/i18n/messages/gu.json
index 2276270c4b..1035db923d 100644
--- a/src/i18n/messages/gu.json
+++ b/src/i18n/messages/gu.json
@@ -7812,6 +7812,10 @@
         "label": "કમ્પેક્ટ કરવા માટે ન્યૂનતમ પંક્તિઓ",
         "description": "ટેબ્યુલર કમ્પેક્શન ટ્રિગર કરવા માટે સજાતીય JSON એરેમાં જરૂરી ન્યૂનતમ પંક્તિઓ. ડિફોલ્ટ: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "સિસ્ટમ પ્રોમ્પ્ટ સાચવો"
       },
diff --git a/src/i18n/messages/he.json b/src/i18n/messages/he.json
index df203e014d..1d8cb4679c 100644
--- a/src/i18n/messages/he.json
+++ b/src/i18n/messages/he.json
@@ -7812,6 +7812,10 @@
         "label": "מינימום שורות לכיווץ",
         "description": "מספר השורות המינימלי במערך JSON הומוגני הנדרש להפעלת כיווץ טבלאי. ברירת מחדל: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "שמור על הנחיית המערכת"
       },
diff --git a/src/i18n/messages/hi.json b/src/i18n/messages/hi.json
index 1f682dc671..5c6e92f1ff 100644
--- a/src/i18n/messages/hi.json
+++ b/src/i18n/messages/hi.json
@@ -7812,6 +7812,10 @@
         "label": "कॉम्पैक्ट करने के लिए न्यूनतम पंक्तियाँ",
         "description": "सारणीबद्ध कॉम्पैक्शन को ट्रिगर करने के लिए सजातीय JSON ऐरे में आवश्यक न्यूनतम पंक्तियाँ। डिफ़ॉल्ट: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "सिस्टम प्रॉम्प्ट सुरक्षित रखें"
       },
diff --git a/src/i18n/messages/hu.json b/src/i18n/messages/hu.json
index 97544437d8..e86fc50a90 100644
--- a/src/i18n/messages/hu.json
+++ b/src/i18n/messages/hu.json
@@ -7812,6 +7812,10 @@
         "label": "Tömörítendő sorok minimális száma",
         "description": "Egy homogén JSON-tömb minimális sorszáma a táblázatos tömörítés indításához. Alapértelmezett: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Rendszerüzenet megőrzése"
       },
diff --git a/src/i18n/messages/id.json b/src/i18n/messages/id.json
index 551443ad7d..570e308419 100644
--- a/src/i18n/messages/id.json
+++ b/src/i18n/messages/id.json
@@ -7812,6 +7812,10 @@
         "label": "Baris minimum untuk dipadatkan",
         "description": "Jumlah baris minimum dalam array JSON homogen yang diperlukan untuk memicu pemadatan tabular. Default: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Pertahankan prompt sistem"
       },
diff --git a/src/i18n/messages/in.json b/src/i18n/messages/in.json
index 97dd33dba1..78f5e27275 100644
--- a/src/i18n/messages/in.json
+++ b/src/i18n/messages/in.json
@@ -7812,6 +7812,10 @@
         "label": "Baris minimum untuk dipadatkan",
         "description": "Jumlah baris minimum dalam larik JSON homogen yang diperlukan untuk memicu pemadatan tabular. Default: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Pertahankan prompt sistem"
       },
diff --git a/src/i18n/messages/it.json b/src/i18n/messages/it.json
index a5d9884034..d6d556eb2a 100644
--- a/src/i18n/messages/it.json
+++ b/src/i18n/messages/it.json
@@ -7812,6 +7812,10 @@
         "label": "Righe minime da compattare",
         "description": "Numero minimo di righe in un array JSON omogeneo richiesto per attivare la compattazione tabulare. Predefinito: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Preserva prompt di sistema"
       },
diff --git a/src/i18n/messages/ja.json b/src/i18n/messages/ja.json
index e6e541ebd5..b6a60691c7 100644
--- a/src/i18n/messages/ja.json
+++ b/src/i18n/messages/ja.json
@@ -7812,6 +7812,10 @@
         "label": "圧縮する最小行数",
         "description": "表形式の圧縮をトリガーするために必要な、同質なJSON配列の最小行数。デフォルト: 8。"
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "システムプロンプトを保持"
       },
diff --git a/src/i18n/messages/ko.json b/src/i18n/messages/ko.json
index 7c57f66bd9..49648edb0a 100644
--- a/src/i18n/messages/ko.json
+++ b/src/i18n/messages/ko.json
@@ -7812,6 +7812,10 @@
         "label": "압축할 최소 행 수",
         "description": "테이블 형식 압축을 트리거하는 데 필요한 동질적 JSON 배열의 최소 행 수입니다. 기본값: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "시스템 프롬프트 유지"
       },
diff --git a/src/i18n/messages/mr.json b/src/i18n/messages/mr.json
index ec5a1f0db9..fd3648c190 100644
--- a/src/i18n/messages/mr.json
+++ b/src/i18n/messages/mr.json
@@ -7812,6 +7812,10 @@
         "label": "कॉम्पॅक्ट करण्यासाठी किमान ओळी",
         "description": "टॅब्युलर कॉम्पॅक्शन ट्रिगर करण्यासाठी एकसमान JSON ॲरेमध्ये आवश्यक असलेल्या किमान ओळी. डीफॉल्ट: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "सिस्टम प्रॉम्प्ट जतन करा"
       },
diff --git a/src/i18n/messages/ms.json b/src/i18n/messages/ms.json
index 708c2b41bf..bc2a159b25 100644
--- a/src/i18n/messages/ms.json
+++ b/src/i18n/messages/ms.json
@@ -7812,6 +7812,10 @@
         "label": "Baris minimum untuk dipadatkan",
         "description": "Baris minimum dalam tatasusunan JSON homogen yang diperlukan untuk mencetuskan pemadatan jadual. Lalai: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Kekalkan gesaan sistem"
       },
diff --git a/src/i18n/messages/nl.json b/src/i18n/messages/nl.json
index e5fb7840b3..8529dc71db 100644
--- a/src/i18n/messages/nl.json
+++ b/src/i18n/messages/nl.json
@@ -7812,6 +7812,10 @@
         "label": "Minimum aantal rijen om te compacteren",
         "description": "Minimum aantal rijen in een homogene JSON-array dat vereist is om tabulaire compactie te activeren. Standaard: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Systeemprompt behouden"
       },
diff --git a/src/i18n/messages/no.json b/src/i18n/messages/no.json
index 95c88da0d7..bd779d1fea 100644
--- a/src/i18n/messages/no.json
+++ b/src/i18n/messages/no.json
@@ -7812,6 +7812,10 @@
         "label": "Minimum rader å komprimere",
         "description": "Minimum antall rader i et homogent JSON-array som kreves for å utløse tabulær komprimering. Standard: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Bevar system-prompt"
       },
diff --git a/src/i18n/messages/phi.json b/src/i18n/messages/phi.json
index 30fa94e341..3a3098b0e6 100644
--- a/src/i18n/messages/phi.json
+++ b/src/i18n/messages/phi.json
@@ -7812,6 +7812,10 @@
         "label": "Minimum na row na iko-compact",
         "description": "Minimum na row sa isang homogeneous na JSON array na kinakailangan upang ma-trigger ang tabular compaction. Default: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Panatilihin ang system prompt"
       },
diff --git a/src/i18n/messages/pl.json b/src/i18n/messages/pl.json
index 55eb9a29aa..7b3db8339e 100644
--- a/src/i18n/messages/pl.json
+++ b/src/i18n/messages/pl.json
@@ -7812,6 +7812,10 @@
         "label": "Minimalna liczba wierszy do kompaktowania",
         "description": "Minimalna liczba wierszy w jednorodnej tablicy JSON wymagana do uruchomienia kompaktowania tabelarycznego. Domyślnie: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Zachowaj prompt systemowy"
       },
diff --git a/src/i18n/messages/pt-BR.json b/src/i18n/messages/pt-BR.json
index 9b004e985f..1b2dbe9ea2 100644
--- a/src/i18n/messages/pt-BR.json
+++ b/src/i18n/messages/pt-BR.json
@@ -7802,6 +7802,10 @@
         "label": "Mínimo de linhas para compactar",
         "description": "Mínimo de linhas em um array JSON homogêneo necessárias para acionar a compactação tabular. Padrão: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Preservar prompt do sistema"
       },
diff --git a/src/i18n/messages/pt.json b/src/i18n/messages/pt.json
index 29b7ba3657..b5fb8a7380 100644
--- a/src/i18n/messages/pt.json
+++ b/src/i18n/messages/pt.json
@@ -7812,6 +7812,10 @@
         "label": "Mínimo de linhas a compactar",
         "description": "Número mínimo de linhas num array JSON homogéneo necessário para acionar a compactação tabular. Predefinição: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Preservar prompt do sistema"
       },
diff --git a/src/i18n/messages/ro.json b/src/i18n/messages/ro.json
index 78c562fa21..843c7ef3fa 100644
--- a/src/i18n/messages/ro.json
+++ b/src/i18n/messages/ro.json
@@ -7812,6 +7812,10 @@
         "label": "Număr minim de rânduri de compactat",
         "description": "Numărul minim de rânduri dintr-un tablou JSON omogen necesar pentru a declanșa compactarea tabulară. Implicit: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Păstrează promptul de sistem"
       },
diff --git a/src/i18n/messages/ru.json b/src/i18n/messages/ru.json
index db18a4bb11..55292cd9d3 100644
--- a/src/i18n/messages/ru.json
+++ b/src/i18n/messages/ru.json
@@ -7812,6 +7812,10 @@
         "label": "Минимальное число строк для компактизации",
         "description": "Минимальное количество строк в однородном массиве JSON, необходимое для запуска табличной компактизации. По умолчанию: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Сохранять системный промпт"
       },
diff --git a/src/i18n/messages/sk.json b/src/i18n/messages/sk.json
index 49e825255a..ee9c62f677 100644
--- a/src/i18n/messages/sk.json
+++ b/src/i18n/messages/sk.json
@@ -7812,6 +7812,10 @@
         "label": "Minimálny počet riadkov na zhustenie",
         "description": "Minimálny počet riadkov v homogénnom JSON poli potrebný na spustenie tabuľkového zhustenia. Predvolené: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Zachovať systémový prompt"
       },
diff --git a/src/i18n/messages/sv.json b/src/i18n/messages/sv.json
index d13c7cbea5..ba6bbbe891 100644
--- a/src/i18n/messages/sv.json
+++ b/src/i18n/messages/sv.json
@@ -7812,6 +7812,10 @@
         "label": "Minsta antal rader att komprimera",
         "description": "Minsta antal rader i en homogen JSON-array som krävs för att utlösa tabellkomprimering. Standard: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Bevara systemprompt"
       },
diff --git a/src/i18n/messages/sw.json b/src/i18n/messages/sw.json
index c5e6c4fa90..a3165d7dd8 100644
--- a/src/i18n/messages/sw.json
+++ b/src/i18n/messages/sw.json
@@ -7812,6 +7812,10 @@
         "label": "Kiwango cha chini cha safu mlalo za kubana",
         "description": "Kiwango cha chini cha safu mlalo katika safu ya JSON inayofanana inayohitajika ili kuanzisha ubana wa jedwali. Chaguo-msingi: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Hifadhi kidokezo cha mfumo"
       },
diff --git a/src/i18n/messages/ta.json b/src/i18n/messages/ta.json
index 87d7587709..5187bea668 100644
--- a/src/i18n/messages/ta.json
+++ b/src/i18n/messages/ta.json
@@ -7812,6 +7812,10 @@
         "label": "சுருக்குவதற்கான குறைந்தபட்ச வரிசைகள்",
         "description": "அட்டவணை சுருக்கத்தைத் தூண்டுவதற்கு ஒரே மாதிரியான JSON வரிசையில் தேவைப்படும் குறைந்தபட்ச வரிசைகள். இயல்புநிலை: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "சிஸ்டம் பிராம்ப்ட்டைப் பாதுகாக்கவும்"
       },
diff --git a/src/i18n/messages/te.json b/src/i18n/messages/te.json
index 8e6747c73b..a4de572e49 100644
--- a/src/i18n/messages/te.json
+++ b/src/i18n/messages/te.json
@@ -7812,6 +7812,10 @@
         "label": "కంపాక్ట్ చేయడానికి కనీస అడ్డు వరుసలు",
         "description": "టేబులర్ కంపాక్షన్‌ను ట్రిగ్గర్ చేయడానికి సజాతీయ JSON అరేలో అవసరమైన కనీస అడ్డు వరుసలు. డిఫాల్ట్: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "సిస్టమ్ ప్రాంప్ట్‌ను భద్రపరచండి"
       },
diff --git a/src/i18n/messages/th.json b/src/i18n/messages/th.json
index 26957baf01..81f03e11c3 100644
--- a/src/i18n/messages/th.json
+++ b/src/i18n/messages/th.json
@@ -7812,6 +7812,10 @@
         "label": "จำนวนแถวขั้นต่ำที่จะกระชับข้อมูล",
         "description": "จำนวนแถวขั้นต่ำในอาร์เรย์ JSON ที่เป็นเนื้อเดียวกันซึ่งจำเป็นต่อการทริกเกอร์การกระชับข้อมูลแบบตาราง ค่าเริ่มต้น: 8"
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "คงพรอมต์ระบบไว้"
       },
diff --git a/src/i18n/messages/tr.json b/src/i18n/messages/tr.json
index c02733a342..00cd54af41 100644
--- a/src/i18n/messages/tr.json
+++ b/src/i18n/messages/tr.json
@@ -7812,6 +7812,10 @@
         "label": "Sıkıştırılacak minimum satır sayısı",
         "description": "Tablosal sıkıştırmayı tetiklemek için homojen bir JSON dizisinde gereken minimum satır sayısı. Varsayılan: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Sistem istemini koru"
       },
diff --git a/src/i18n/messages/uk-UA.json b/src/i18n/messages/uk-UA.json
index b516a2e0ff..bc5082da8c 100644
--- a/src/i18n/messages/uk-UA.json
+++ b/src/i18n/messages/uk-UA.json
@@ -7812,6 +7812,10 @@
         "label": "Мінімальна кількість рядків для компактності",
         "description": "Мінімальна кількість рядків в однорідному масиві JSON, необхідна для запуску табличного ущільнення. За замовчуванням: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Зберігати системний промпт"
       },
diff --git a/src/i18n/messages/ur.json b/src/i18n/messages/ur.json
index 27a788a659..755d3929d0 100644
--- a/src/i18n/messages/ur.json
+++ b/src/i18n/messages/ur.json
@@ -7812,6 +7812,10 @@
         "label": "کمپیکٹ کرنے کے لیے کم از کم قطاریں",
         "description": "ٹیبلر کمپیکشن کو متحرک کرنے کے لیے ایک یکساں JSON اری میں مطلوبہ کم از کم قطاریں۔ ڈیفالٹ: 8۔"
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "سسٹم پرامپٹ کو محفوظ رکھیں"
       },
diff --git a/src/i18n/messages/vi.json b/src/i18n/messages/vi.json
index e376f3c2e6..d4b3f16030 100644
--- a/src/i18n/messages/vi.json
+++ b/src/i18n/messages/vi.json
@@ -7814,6 +7814,10 @@
         "label": "Số hàng tối thiểu để nén",
         "description": "Số hàng tối thiểu trong một mảng JSON đồng nhất để kích hoạt nén dạng bảng. Mặc định: 8."
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "Giữ nguyên prompt hệ thống"
       },
diff --git a/src/i18n/messages/zh-CN.json b/src/i18n/messages/zh-CN.json
index 56680f2ae2..7e0fbfa1c6 100644
--- a/src/i18n/messages/zh-CN.json
+++ b/src/i18n/messages/zh-CN.json
@@ -7812,6 +7812,10 @@
         "label": "压缩所需的最小行数",
         "description": "触发表格压缩所需的同构 JSON 数组的最小行数。默认值: 8。"
       },
+      "compressToolResults": {
+        "label": "主动截断过长的工具结果",
+        "description": "在 Lite 压缩期间截断超过 2,000 个字符的工具结果。当上下文超出模型预算时，紧急溢出保护仍可能裁剪内容。"
+      },
       "preserveSystemPrompt": {
         "label": "保留系统提示词"
       },
diff --git a/src/i18n/messages/zh-TW.json b/src/i18n/messages/zh-TW.json
index 2fe9631367..f8a5261460 100644
--- a/src/i18n/messages/zh-TW.json
+++ b/src/i18n/messages/zh-TW.json
@@ -7812,6 +7812,10 @@
         "label": "最小壓縮行數",
         "description": "觸發表格壓縮所需的同質 JSON 陣列最小行數。預設值：8。"
       },
+      "compressToolResults": {
+        "label": "__MISSING__:Proactively truncate long tool results",
+        "description": "__MISSING__:Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget."
+      },
       "preserveSystemPrompt": {
         "label": "保留系統提示詞"
       },
diff --git a/src/lib/db/compression.ts b/src/lib/db/compression.ts
index d927aa2467..7dd03bdbb8 100644
--- a/src/lib/db/compression.ts
+++ b/src/lib/db/compression.ts
@@ -616,6 +616,7 @@ export async function getCompressionSettings(): Promise<CompressionConfig> {
     stackedPipeline: normalizeStackedPipeline(undefined),
     aggressive: normalizeAggressiveConfig(undefined),
     ultra: normalizeUltraConfig(undefined),
+    lite: { compressToolResults: true },
     headroom: normalizeHeadroomConfig(undefined),
     ...buildDetailConfigDefaults(),
     contextBudget: normalizeContextBudgetConfig(undefined),
@@ -726,6 +727,9 @@ export async function getCompressionSettings(): Promise<CompressionConfig> {
       case "ultraConfig":
         config.ultra = normalizeUltraConfig(parsed);
         break;
+      case "lite":
+        config.lite = { compressToolResults: toRecord(parsed).compressToolResults !== false };
+        break;
       case "headroom":
       case "headroomConfig":
         config.headroom = normalizeHeadroomConfig(parsed);
diff --git a/src/shared/components/compression/EngineConfigPage.tsx b/src/shared/components/compression/EngineConfigPage.tsx
index 5c1981a4ec..36e45f5541 100644
--- a/src/shared/components/compression/EngineConfigPage.tsx
+++ b/src/shared/components/compression/EngineConfigPage.tsx
@@ -23,10 +23,12 @@ interface EngineEntry {
 // (/dashboard/context/settings, the `engines` map); only these have a place to
 // persist the extra per-engine fields edited on this page. session-dedup and ccr
 // joined headroom in #8388 (they previously rendered a real, editable detail form
-// with no Save affordance — edits vanished on reload). Other structural engines
-// (lite, llmlingua, relevance) still have no dedicated sub-object — their page
+// with no Save affordance — edits vanished on reload). lite gained a dedicated
+// sub-object with the compressToolResults toggle. Other structural engines
+// (llmlingua, relevance) still have no dedicated sub-object — their page
 // keeps the detail form + preview but has nothing extra to persist yet.
 const SETTINGS_SUBOBJECT: Record<string, string> = {
+  lite: "lite",
   aggressive: "aggressive",
   ultra: "ultra",
   headroom: "headroom",
@@ -200,8 +202,12 @@ export function EngineConfigPage({ engineId }: { engineId: string }) {
       return;
     }
     // Strip the `enabled` key — engine on/off is the panel's responsibility.
-    const { enabled: _ignored, ...detail } = configState;
+    const { enabled: _ignored, ...formDetail } = configState;
     void _ignored;
+    const detail =
+      engineId === "lite"
+        ? { compressToolResults: formDetail.compressToolResults !== false }
+        : formDetail;
     setSaving(true);
     setSaveError(null);
     try {
diff --git a/src/shared/validation/compressionConfigSchemas.ts b/src/shared/validation/compressionConfigSchemas.ts
index 74c56d275a..e644fcb688 100644
--- a/src/shared/validation/compressionConfigSchemas.ts
+++ b/src/shared/validation/compressionConfigSchemas.ts
@@ -309,6 +309,12 @@ export const STACKED_PIPELINE_ENGINE_INTENSITIES: Record<string, readonly string
   ultra: ["ultra"],
 };
 
+export const liteConfigSchema = z
+  .object({
+    compressToolResults: z.boolean().optional(),
+  })
+  .strict();
+
 export const engineToggleSchema = z.object({
   enabled: z.boolean(),
   level: z.string().optional(),
@@ -361,6 +367,7 @@ export const compressionSettingsUpdateSchema = z
     languageConfig: languageConfigSchema.optional(),
     aggressive: aggressiveConfigSchema.optional(),
     ultra: ultraConfigSchema.optional(),
+    lite: liteConfigSchema.optional(),
     headroom: headroomConfigSchema.optional(),
     sessionDedup: sessionDedupConfigSchema.optional(),
     ccr: ccrConfigSchema.optional(),
diff --git a/tests/unit/compression/db.test.ts b/tests/unit/compression/db.test.ts
index 20ba863dbd..1861e71dcf 100644
--- a/tests/unit/compression/db.test.ts
+++ b/tests/unit/compression/db.test.ts
@@ -41,6 +41,7 @@ describe("getCompressionSettings", () => {
     assert.equal(typeof settings.cacheMinutes, "number");
     assert.equal(typeof settings.preserveSystemPrompt, "boolean");
     assert.equal(typeof settings.comboOverrides, "object");
+    assert.equal(typeof settings.lite, "object");
     assert.equal(typeof settings.ultra, "object");
   });
 
@@ -54,6 +55,7 @@ describe("getCompressionSettings", () => {
     assert.equal(settings.preserveSystemPromptMode, "always");
     assert.deepEqual(settings.liveZone, { enabled: false });
     assert.deepEqual(settings.comboOverrides, {});
+    assert.equal(settings.lite?.compressToolResults, true);
     assert.equal(settings.ultra?.enabled, false);
     assert.equal(settings.ultra?.compressionRate, 0.5);
     assert.equal(settings.ultra?.minScoreThreshold, 0.3);
@@ -71,6 +73,14 @@ describe("updateCompressionSettings", () => {
     await updateCompressionSettings({ enabled: false } as any);
   });
 
+  it("persists the Lite proactive tool-result truncation switch across reload", async () => {
+    await updateCompressionSettings({ lite: { compressToolResults: false } });
+    core.resetDbInstance();
+
+    const settings = await getCompressionSettings();
+    assert.equal(settings.lite?.compressToolResults, false);
+  });
+
   it("updates defaultMode", async () => {
     await updateCompressionSettings({ defaultMode: "lite" } as any);
     const settings = await getCompressionSettings();
diff --git a/tests/unit/compression/engine-registry.test.ts b/tests/unit/compression/engine-registry.test.ts
index 6dffe20278..f70571a826 100644
--- a/tests/unit/compression/engine-registry.test.ts
+++ b/tests/unit/compression/engine-registry.test.ts
@@ -80,10 +80,20 @@ describe("compression engine registry contract", () => {
     // summarizer/threshold fields it previously leaked.
     const liteSchema = liteEngine.getConfigSchema();
     assert.ok(liteSchema.some((field) => field.key === "preserveSystemPrompt"));
+    assert.ok(
+      liteSchema.some((field) => field.key === "compressToolResults" && field.defaultValue === true)
+    );
     assert.ok(!liteSchema.some((field) => field.key === "maxTokensPerMessage"));
     assert.ok(!liteSchema.some((field) => field.key === "summarizerEnabled"));
-    assert.equal(liteEngine.validateConfig({ preserveSystemPrompt: true }).valid, true);
+    assert.equal(
+      liteEngine.validateConfig({
+        preserveSystemPrompt: true,
+        compressToolResults: false,
+      }).valid,
+      true
+    );
     assert.equal(liteEngine.validateConfig({ preserveSystemPrompt: "yes" }).valid, false);
+    assert.equal(liteEngine.validateConfig({ compressToolResults: "no" }).valid, false);
     assert.equal(cavemanEngine.validateConfig({ intensity: "full" }).valid, true);
     assert.equal(cavemanEngine.validateConfig({ intensity: "bad" }).valid, false);
     assert.equal(realRtkEngine.validateConfig({ maxLinesPerResult: 20 }).valid, true);
diff --git a/tests/unit/compression/headroom-minrows-persist-8056.test.ts b/tests/unit/compression/headroom-minrows-persist-8056.test.ts
index 651ef316cf..de52eb5b11 100644
--- a/tests/unit/compression/headroom-minrows-persist-8056.test.ts
+++ b/tests/unit/compression/headroom-minrows-persist-8056.test.ts
@@ -67,6 +67,20 @@ function baseConfig(overrides: Partial<CompressionConfig> = {}): CompressionConf
 }
 
 describe("#8056 headroom minRows persistence", () => {
+  it("schema accepts Lite proactive tool-result truncation detail", () => {
+    const result = compressionSettingsUpdateSchema.safeParse({
+      lite: { compressToolResults: false },
+    });
+    assert.equal(result.success, true, JSON.stringify(result.error?.issues));
+  });
+
+  it("schema rejects a non-boolean Lite proactive tool-result truncation detail", () => {
+    const result = compressionSettingsUpdateSchema.safeParse({
+      lite: { compressToolResults: "no" },
+    });
+    assert.equal(result.success, false);
+  });
+
   it("schema accepts headroom.minRows=5", () => {
     const result = compressionSettingsUpdateSchema.safeParse({
       headroom: { minRows: 5 },
diff --git a/tests/unit/compression/lite.test.ts b/tests/unit/compression/lite.test.ts
index 26707ab938..6decf519c5 100644
--- a/tests/unit/compression/lite.test.ts
+++ b/tests/unit/compression/lite.test.ts
@@ -194,6 +194,86 @@ describe("replaceImageUrls", () => {
   });
 });
 
+describe("stacked Lite precedence (global config vs explicit step)", () => {
+  const toolContent = `${"word ".repeat(500)}TAIL`;
+  const liteStep = { engine: "lite" };
+  const baseConfig = {
+    enabled: true,
+    defaultMode: "lite",
+    autoTriggerTokens: 0,
+    cacheMinutes: 5,
+    preserveSystemPrompt: true,
+    comboOverrides: {},
+    engines: {},
+    activeComboId: null,
+  };
+
+  it("global compressToolResults=false disables truncation when no step override", () => {
+    const result = applyCompression(
+      { messages: [{ role: "tool", content: toolContent }] },
+      "stacked",
+      {
+        config: {
+          ...baseConfig,
+          lite: { compressToolResults: false },
+          stackedPipeline: [liteStep],
+        },
+      }
+    );
+    const messages = result.body.messages as Array<{ content: string }>;
+    assert.equal(messages[0].content, toolContent.trimEnd());
+    assert.ok(messages[0].content.length > 2000);
+    assert.doesNotMatch(messages[0].content, /\[truncated\]/);
+    assert.ok(!result.stats?.techniquesUsed.includes("tool-compress"));
+  });
+
+  it("explicit step compressToolResults=true overrides global false", () => {
+    const result = applyCompression(
+      { messages: [{ role: "tool", content: toolContent }] },
+      "stacked",
+      {
+        config: {
+          ...baseConfig,
+          lite: { compressToolResults: false },
+          stackedPipeline: [{ engine: "lite", config: { compressToolResults: true } }],
+        },
+      }
+    );
+    const messages = result.body.messages as Array<{ content: string }>;
+    assert.match(messages[0].content, /\.\.\.\[truncated\]$/);
+    assert.ok(messages[0].content.length < toolContent.length);
+    assert.ok(result.stats?.techniquesUsed.includes("tool-compress"));
+  });
+
+  it("explicit step compressToolResults=false overrides global true/default", () => {
+    const result = applyCompression(
+      { messages: [{ role: "tool", content: toolContent }] },
+      "stacked",
+      {
+        config: {
+          ...baseConfig,
+          lite: { compressToolResults: true },
+          stackedPipeline: [{ engine: "lite", config: { compressToolResults: false } }],
+        },
+      }
+    );
+    const messages = result.body.messages as Array<{ content: string }>;
+    assert.equal(messages[0].content, toolContent.trimEnd());
+    assert.doesNotMatch(messages[0].content, /\[truncated\]/);
+    assert.ok(!result.stats?.techniquesUsed.includes("tool-compress"));
+  });
+
+  it("stacked default (no lite config) keeps truncation enabled", () => {
+    const result = applyCompression(
+      { messages: [{ role: "tool", content: toolContent }] },
+      "stacked",
+      { config: { ...baseConfig, stackedPipeline: [liteStep] } }
+    );
+    const messages = result.body.messages as Array<{ content: string }>;
+    assert.match(messages[0].content, /\.\.\.\[truncated\]$/);
+  });
+});
+
 describe("applyLiteCompression", () => {
   it("applies all techniques that match", () => {
     const body = {
@@ -211,6 +291,43 @@ describe("applyLiteCompression", () => {
     assert.ok(result.stats.savingsPercent > 0);
   });
 
+  it("keeps proactive tool-result truncation enabled when Lite detail config is missing", () => {
+    const toolContent = `${"word ".repeat(500)}TAIL`;
+    const result = applyCompression({ messages: [{ role: "tool", content: toolContent }] }, "lite");
+    const messages = result.body.messages as Array<{ content: string }>;
+
+    assert.match(messages[0].content, /\.\.\.\[truncated\]$/);
+    assert.ok(messages[0].content.length < toolContent.length);
+  });
+
+  it("can disable only proactive tool-result truncation while other Lite transforms still apply", () => {
+    const toolContent = `${"word ".repeat(500)}TAIL   `;
+    const result = applyCompression(
+      { messages: [{ role: "tool", content: toolContent }] },
+      "lite",
+      {
+        config: {
+          enabled: true,
+          defaultMode: "lite",
+          autoTriggerTokens: 0,
+          cacheMinutes: 5,
+          preserveSystemPrompt: true,
+          comboOverrides: {},
+          engines: {},
+          activeComboId: null,
+          lite: { compressToolResults: false },
+        },
+      }
+    );
+    const messages = result.body.messages as Array<{ content: string }>;
+
+    assert.equal(messages[0].content, toolContent.trimEnd());
+    assert.ok(messages[0].content.length > 2000);
+    assert.doesNotMatch(messages[0].content, /\[truncated\]/);
+    assert.ok(result.stats?.techniquesUsed.includes("whitespace"));
+    assert.ok(!result.stats?.techniquesUsed.includes("tool-compress"));
+  });
+
   it("preserves system prompt text when preserveSystemPrompt is enabled", () => {
     const body = {
       messages: [
diff --git a/tests/unit/ui/engineConfigPage.test.tsx b/tests/unit/ui/engineConfigPage.test.tsx
index 701e746ba6..824a806d09 100644
--- a/tests/unit/ui/engineConfigPage.test.tsx
+++ b/tests/unit/ui/engineConfigPage.test.tsx
@@ -421,6 +421,83 @@ describe("EngineConfigPage", () => {
     expect(container.parentNode).toBeTruthy();
   });
 
+  it("loads and saves the Lite proactive truncation switch with emergency-trim copy", async () => {
+    const settingsPuts: Array<Record<string, unknown>> = [];
+    vi.spyOn(globalThis, "fetch").mockImplementation(
+      async (input: RequestInfo | URL, init?: RequestInit) => {
+        const url = input.toString();
+        if (url.includes("/api/compression/engines")) {
+          return new Response(
+            JSON.stringify({
+              engines: [
+                {
+                  id: "lite",
+                  name: "Lite",
+                  description: "Lite engine",
+                  icon: "compress",
+                  stackable: true,
+                  stackPriority: 5,
+                  metadata: { description: "Lite metadata" },
+                  configSchema: [
+                    {
+                      key: "compressToolResults",
+                      type: "boolean",
+                      label: "Proactively truncate long tool results",
+                      description:
+                        "Truncates tool results over 2,000 characters during Lite compression. Emergency overflow protection may still trim content when the context exceeds the model budget.",
+                      defaultValue: true,
+                    },
+                  ],
+                },
+              ],
+            }),
+            { status: 200, headers: { "Content-Type": "application/json" } }
+          );
+        }
+        if (url.includes("/api/settings/compression")) {
+          if (init?.method === "PUT") {
+            settingsPuts.push(JSON.parse(init.body as string) as Record<string, unknown>);
+          }
+          return new Response(JSON.stringify({ lite: { compressToolResults: false } }), {
+            status: 200,
+            headers: { "Content-Type": "application/json" },
+          });
+        }
+        if (url.includes("/api/context/analytics/engine")) {
+          return new Response(JSON.stringify(ANALYTICS_PAYLOAD), {
+            status: 200,
+            headers: { "Content-Type": "application/json" },
+          });
+        }
+        return new Response(JSON.stringify({}), { status: 404 });
+      }
+    );
+
+    const { EngineConfigPage } =
+      await import("../../../src/shared/components/compression/EngineConfigPage");
+    let container!: HTMLElement;
+    await act(async () => {
+      container = mountInContainer(<EngineConfigPage engineId="lite" />);
+      await Promise.resolve();
+    });
+
+    const toggle = container.querySelector("input[type='checkbox']") as HTMLInputElement | null;
+    expect(toggle).not.toBeNull();
+    expect(toggle?.checked).toBe(false);
+    expect(container.textContent).toContain("Emergency overflow protection may still trim content");
+
+    const saveButton = Array.from(container.querySelectorAll("button")).find((button) =>
+      button.textContent?.includes("Save")
+    );
+    expect(saveButton).toBeTruthy();
+    await act(async () => {
+      saveButton?.click();
+      await Promise.resolve();
+    });
+
+    expect(settingsPuts).toContainEqual({ lite: { compressToolResults: false } });
+  });
+
   it("#8056: headroom minRows is persistable — Save PUTs headroom:{minRows:5}", async () => {
     const settingsPuts: { body: Record<string, unknown> }[] = [];
     vi.spyOn(globalThis, "fetch").mockImplementation(