diff --git a/packages/core/src/settings-schema.ts b/packages/core/src/settings-schema.ts
index 9cc5ef51f..4e9f60fb1 100644
--- a/packages/core/src/settings-schema.ts
+++ b/packages/core/src/settings-schema.ts
@@ -311,6 +311,9 @@ export const DEFAULT_PROJECT_SETTINGS = {
   reflectionAfterTask: true,
   reviewHandoffPolicy: "disabled",
   showQuickChatFAB: false,
+  chatRoomRecentVerbatimMessages: 12,
+  chatRoomCompactionFetchLimit: 80,
+  chatRoomSummaryMaxChars: 1_500,
   researchSettings: {
     enabled: true,
     searchProvider: undefined,
diff --git a/packages/core/src/types.ts b/packages/core/src/types.ts
index 2ea90fa77..a00b0b76d 100644
--- a/packages/core/src/types.ts
+++ b/packages/core/src/types.ts
@@ -2652,6 +2652,15 @@ export interface ProjectSettings {
    *  When false, the FAB is hidden but chat remains accessible via the More menu.
    *  Default: false. */
   showQuickChatFAB?: boolean;
+  /** Number of most-recent chat-room messages kept verbatim in the responder transcript.
+   *  Older messages are compacted into a summary block. Default: 12. */
+  chatRoomRecentVerbatimMessages?: number;
+  /** Upper bound on messages fetched from the room store for compaction consideration.
+   *  Default: 80. */
+  chatRoomCompactionFetchLimit?: number;
+  /** Hard cap on the synthesized "Earlier room context" summary block.
+   *  Default: 1500. */
+  chatRoomSummaryMaxChars?: number;
 }
 
 /**