diff --git a/src/agents/memory-search.test.ts b/src/agents/memory-search.test.ts
index a49aefa4634..4d960aad6e9 100644
--- a/src/agents/memory-search.test.ts
+++ b/src/agents/memory-search.test.ts
@@ -170,6 +170,7 @@ describe("memory search config", () => {
     expect(resolved?.sync.sessions).toEqual({
       deltaBytes: 100000,
       deltaMessages: 50,
+      postCompactionForce: true,
     });
   });
 
diff --git a/src/agents/memory-search.ts b/src/agents/memory-search.ts
index a8aadc15b2c..51de5d72863 100644
--- a/src/agents/memory-search.ts
+++ b/src/agents/memory-search.ts
@@ -52,6 +52,7 @@ export type ResolvedMemorySearchConfig = {
     sessions: {
       deltaBytes: number;
       deltaMessages: number;
+      postCompactionForce: boolean;
     };
   };
   query: {
@@ -229,6 +230,10 @@ function mergeConfig(
         overrides?.sync?.sessions?.deltaMessages ??
         defaults?.sync?.sessions?.deltaMessages ??
         DEFAULT_SESSION_DELTA_MESSAGES,
+      postCompactionForce:
+        overrides?.sync?.sessions?.postCompactionForce ??
+        defaults?.sync?.sessions?.postCompactionForce ??
+        true,
     },
   };
   const query = {
@@ -296,6 +301,7 @@ function mergeConfig(
   );
   const deltaBytes = clampInt(sync.sessions.deltaBytes, 0, Number.MAX_SAFE_INTEGER);
   const deltaMessages = clampInt(sync.sessions.deltaMessages, 0, Number.MAX_SAFE_INTEGER);
+  const postCompactionForce = sync.sessions.postCompactionForce ?? true;
   return {
     enabled,
     sources,
@@ -315,6 +321,7 @@ function mergeConfig(
       sessions: {
         deltaBytes,
         deltaMessages,
+        postCompactionForce,
       },
     },
     query: {
diff --git a/src/config/schema.help.ts b/src/config/schema.help.ts
index 529911d6e9e..e703c42aec6 100644
--- a/src/config/schema.help.ts
+++ b/src/config/schema.help.ts
@@ -842,6 +842,8 @@ export const FIELD_HELP: Record<string, string> = {
     "Requires at least this many newly appended bytes before session transcript changes trigger reindex (default: 100000). Increase to reduce frequent small reindexes, or lower for faster transcript freshness.",
   "agents.defaults.memorySearch.sync.sessions.deltaMessages":
     "Requires at least this many appended transcript messages before reindex is triggered (default: 50). Lower this for near-real-time transcript recall, or raise it to reduce indexing churn.",
+  "agents.defaults.memorySearch.sync.sessions.postCompactionForce":
+    "Forces a session memory-search reindex after compaction-triggered transcript updates (default: true). Keep enabled when compacted summaries must be immediately searchable, or disable to reduce write-time indexing pressure.",
   "agents.defaults.compaction.recentTurnsPreserve":
     "Number of most recent user/assistant turns kept verbatim outside safeguard summarization (default: 3). Raise this to preserve exact recent dialogue context, or lower it to maximize compaction savings.",
   "agents.defaults.compaction.postIndexSync":
diff --git a/src/config/schema.labels.ts b/src/config/schema.labels.ts
index 05a4f3401a5..405a204d8cf 100644
--- a/src/config/schema.labels.ts
+++ b/src/config/schema.labels.ts
@@ -311,6 +311,8 @@ export const FIELD_LABELS: Record<string, string> = {
   "agents.defaults.memorySearch.sync.watchDebounceMs": "Memory Watch Debounce (ms)",
   "agents.defaults.memorySearch.sync.sessions.deltaBytes": "Session Delta Bytes",
   "agents.defaults.memorySearch.sync.sessions.deltaMessages": "Session Delta Messages",
+  "agents.defaults.memorySearch.sync.sessions.postCompactionForce":
+    "Force Reindex After Compaction",
   "agents.defaults.compaction.recentTurnsPreserve": "Compaction Preserve Recent Turns",
   "agents.defaults.compaction.postIndexSync": "Compaction Post-Index Sync",
   "agents.defaults.compaction.qualityGuard.enabled": "Compaction Quality Guard",
diff --git a/src/config/types.tools.ts b/src/config/types.tools.ts
index 492282f2397..23554558510 100644
--- a/src/config/types.tools.ts
+++ b/src/config/types.tools.ts
@@ -377,6 +377,8 @@ export type MemorySearchConfig = {
       deltaBytes?: number;
       /** Minimum appended JSONL lines before session transcripts are reindexed. */
       deltaMessages?: number;
+      /** Force session reindex after compaction-triggered transcript updates (default: true). */
+      postCompactionForce?: boolean;
     };
   };
   /** Query behavior. */
diff --git a/src/config/zod-schema.agent-runtime.ts b/src/config/zod-schema.agent-runtime.ts
index 9df0776b956..69b0ca89135 100644
--- a/src/config/zod-schema.agent-runtime.ts
+++ b/src/config/zod-schema.agent-runtime.ts
@@ -623,6 +623,7 @@ export const MemorySearchSchema = z
           .object({
             deltaBytes: z.number().int().nonnegative().optional(),
             deltaMessages: z.number().int().nonnegative().optional(),
+            postCompactionForce: z.boolean().optional(),
           })
           .strict()
           .optional(),