diff --git a/src/store.ts b/src/store.ts
index 454141e..b1c0cf7 100644
--- a/src/store.ts
+++ b/src/store.ts
@@ -158,8 +158,58 @@ export class MemoryStore {
   private ftsIndexCreated = false;
   private lastFtsError: string | null = null;
 
+  // Per-ID mutex locks to prevent concurrent delete+add in update()
+  private updateLocks = new Map<string, Promise<void>>();
+  // Global write lock for bulkDelete to prevent concurrent updates
+  private bulkDeleteLock: Promise<void> = Promise.resolve();
+
   constructor(private readonly config: StoreConfig) { }
 
+  /**
+   * Per-ID mutex: serializes concurrent update() calls on the same memory ID.
+   * Uses Promise chaining — no external mutex library needed.
+   */
+  private async withUpdateLock<T>(id: string, fn: () => Promise<T>): Promise<T> {
+    // Wait for any in-progress bulkDelete to finish first
+    await this.bulkDeleteLock;
+
+    const prev = this.updateLocks.get(id) ?? Promise.resolve();
+    let resolve: () => void;
+    const next = new Promise<void>(r => { resolve = r; });
+    this.updateLocks.set(id, next);
+    try {
+      await prev;
+      return await fn();
+    } finally {
+      resolve!();
+      // Clean up only if no newer lock was queued for this ID
+      if (this.updateLocks.get(id) === next) {
+        this.updateLocks.delete(id);
+      }
+    }
+  }
+
+  /**
+   * Global write lock for bulkDelete: blocks all concurrent update() calls
+   * while bulk deletion is in progress.
+   */
+  private async withBulkDeleteLock<T>(fn: () => Promise<T>): Promise<T> {
+    const prev = this.bulkDeleteLock;
+    let resolve: () => void;
+    this.bulkDeleteLock = new Promise<void>(r => { resolve = r; });
+    try {
+      await prev;
+      // Also wait for all in-flight per-ID update locks to drain
+      const pending = Array.from(this.updateLocks.values());
+      if (pending.length > 0) {
+        await Promise.all(pending);
+      }
+      return await fn();
+    } finally {
+      resolve!();
+    }
+  }
+
   get dbPath(): string {
     return this.config.dbPath;
   }
@@ -694,7 +744,7 @@ export class MemoryStore {
   ): Promise<MemoryEntry | null> {
     await this.ensureInitialized();
 
-    // Support both full UUID and short prefix (8+ hex chars), same as delete()
+    // Validate ID format before acquiring lock
     const uuidRegex =
       /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i;
     const prefixRegex = /^[0-9a-f]{8,}$/i;
@@ -705,68 +755,71 @@ export class MemoryStore {
       throw new Error(`Invalid memory ID format: ${id}`);
     }
 
-    let rows: any[];
-    if (isFullId) {
-      const safeId = escapeSqlLiteral(id);
-      rows = await this.table!.query()
-        .where(`id = '${safeId}'`)
-        .limit(1)
-        .toArray();
-    } else {
-      // Prefix match
-      const all = await this.table!.query()
-        .select([
-          "id",
-          "text",
-          "vector",
-          "category",
-          "scope",
-          "importance",
-          "timestamp",
-          "metadata",
-        ])
-        .limit(1000)
-        .toArray();
-      rows = all.filter((r: any) => (r.id as string).startsWith(id));
-      if (rows.length > 1) {
-        throw new Error(
-          `Ambiguous prefix "${id}" matches ${rows.length} memories. Use a longer prefix or full ID.`,
-        );
+    // Per-ID mutex: serializes concurrent update() on the same memory
+    return this.withUpdateLock(id, async () => {
+      let rows: any[];
+      if (isFullId) {
+        const safeId = escapeSqlLiteral(id);
+        rows = await this.table!.query()
+          .where(`id = '${safeId}'`)
+          .limit(1)
+          .toArray();
+      } else {
+        // Prefix match
+        const all = await this.table!.query()
+          .select([
+            "id",
+            "text",
+            "vector",
+            "category",
+            "scope",
+            "importance",
+            "timestamp",
+            "metadata",
+          ])
+          .limit(1000)
+          .toArray();
+        rows = all.filter((r: any) => (r.id as string).startsWith(id));
+        if (rows.length > 1) {
+          throw new Error(
+            `Ambiguous prefix "${id}" matches ${rows.length} memories. Use a longer prefix or full ID.`,
+          );
+        }
       }
-    }
 
-    if (rows.length === 0) return null;
+      if (rows.length === 0) return null;
 
-    const row = rows[0];
-    const rowScope = (row.scope as string | undefined) ?? "global";
+      const row = rows[0];
+      const rowScope = (row.scope as string | undefined) ?? "global";
 
-    // Check scope permissions
-    if (
-      scopeFilter &&
-      scopeFilter.length > 0 &&
-      !scopeFilter.includes(rowScope)
-    ) {
-      throw new Error(`Memory ${id} is outside accessible scopes`);
-    }
+      // Check scope permissions
+      if (
+        scopeFilter &&
+        scopeFilter.length > 0 &&
+        !scopeFilter.includes(rowScope)
+      ) {
+        throw new Error(`Memory ${id} is outside accessible scopes`);
+      }
 
-    // Build updated entry, preserving original timestamp
-    const updated: MemoryEntry = {
-      id: row.id as string,
-      text: updates.text ?? (row.text as string),
-      vector: updates.vector ?? Array.from(row.vector as Iterable<number>),
-      category: updates.category ?? (row.category as MemoryEntry["category"]),
-      scope: rowScope,
-      importance: updates.importance ?? Number(row.importance),
-      timestamp: Number(row.timestamp), // preserve original
-      metadata: updates.metadata ?? ((row.metadata as string) || "{}"),
-    };
+      // Build updated entry, preserving original timestamp
+      const updated: MemoryEntry = {
+        id: row.id as string,
+        text: updates.text ?? (row.text as string),
+        vector: updates.vector ?? Array.from(row.vector as Iterable<number>),
+        category: updates.category ?? (row.category as MemoryEntry["category"]),
+        scope: rowScope,
+        importance: updates.importance ?? Number(row.importance),
+        timestamp: Number(row.timestamp), // preserve original
+        metadata: updates.metadata ?? ((row.metadata as string) || "{}"),
+      };
 
-    // LanceDB doesn't support in-place update; delete + re-add
-    const resolvedId = escapeSqlLiteral(row.id as string);
-    await this.table!.delete(`id = '${resolvedId}'`);
-    await this.table!.add([updated]);
+      // LanceDB doesn't support in-place update; delete + re-add
+      const resolvedId = escapeSqlLiteral(row.id as string);
+      await this.table!.delete(`id = '${resolvedId}'`);
+      await this.table!.add([updated]);
 
-    return updated;
+      return updated;
+    });
   }
 
   async bulkDelete(
@@ -775,37 +828,40 @@ export class MemoryStore {
   ): Promise<number> {
     await this.ensureInitialized();
 
-    const conditions: string[] = [];
+    // Global write lock: blocks concurrent update() calls during bulk deletion
+    return this.withBulkDeleteLock(async () => {
+      const conditions: string[] = [];
 
-    if (scopeFilter.length > 0) {
-      const scopeConditions = scopeFilter
-        .map((scope) => `scope = '${escapeSqlLiteral(scope)}'`)
-        .join(" OR ");
-      conditions.push(`(${scopeConditions})`);
-    }
+      if (scopeFilter.length > 0) {
+        const scopeConditions = scopeFilter
+          .map((scope) => `scope = '${escapeSqlLiteral(scope)}'`)
+          .join(" OR ");
+        conditions.push(`(${scopeConditions})`);
+      }
 
-    if (beforeTimestamp) {
-      conditions.push(`timestamp < ${beforeTimestamp}`);
-    }
+      if (beforeTimestamp) {
+        conditions.push(`timestamp < ${beforeTimestamp}`);
+      }
 
-    if (conditions.length === 0) {
-      throw new Error(
-        "Bulk delete requires at least scope or timestamp filter for safety",
-      );
-    }
+      if (conditions.length === 0) {
+        throw new Error(
+          "Bulk delete requires at least scope or timestamp filter for safety",
+        );
+      }
 
-    const whereClause = conditions.join(" AND ");
+      const whereClause = conditions.join(" AND ");
 
-    // Count first
-    const countResults = await this.table!.query().where(whereClause).toArray();
-    const deleteCount = countResults.length;
+      // Count first
+      const countResults = await this.table!.query().where(whereClause).toArray();
+      const deleteCount = countResults.length;
 
-    // Then delete
-    if (deleteCount > 0) {
-      await this.table!.delete(whereClause);
-    }
+      // Then delete
+      if (deleteCount > 0) {
+        await this.table!.delete(whereClause);
+      }
 
-    return deleteCount;
+      return deleteCount;
+    });
   }
 
   get hasFtsSupport(): boolean {
diff --git a/src/tools.ts b/src/tools.ts
index 0575432..29000dc 100644
--- a/src/tools.ts
+++ b/src/tools.ts
@@ -1198,6 +1198,107 @@ export function registerMemoryListTool(
   );
 }
 
+// ============================================================================
+// Purge Scope Tool
+// ============================================================================
+
+export function registerMemoryPurgeScopeTool(
+  api: OpenClawPluginApi,
+  context: ToolContext,
+) {
+  api.registerTool(
+    (toolCtx) => {
+      const agentId = resolveAgentId((toolCtx as any)?.agentId, context.agentId) ?? "main";
+      return {
+        name: "memory_purge_scope",
+        label: "Memory Purge Scope",
+        description:
+          "Permanently delete ALL memories in a specific scope. This is a DESTRUCTIVE and IRREVERSIBLE operation. " +
+          "You must set confirm=true to execute. Use with extreme caution — typically for user/agent cleanup.",
+        parameters: Type.Object({
+          scope: Type.String({
+            description: "The scope to purge (e.g. 'agent:ent_user-xxx_default')",
+          }),
+          confirm: Type.Boolean({
+            description: "Must be true to execute. Safety guard against accidental purge.",
+          }),
+        }),
+        async execute(_toolCallId, params) {
+          const { scope, confirm } = params as {
+            scope: string;
+            confirm: boolean;
+          };
+
+          if (!confirm) {
+            return {
+              content: [
+                {
+                  type: "text",
+                  text: "Purge aborted: confirm must be true to execute this destructive operation.",
+                },
+              ],
+              details: { error: "not_confirmed" },
+            };
+          }
+
+          if (!scope || !scope.trim()) {
+            return {
+              content: [
+                { type: "text", text: "Purge aborted: scope must be a non-empty string." },
+              ],
+              details: { error: "invalid_scope" },
+            };
+          }
+
+          // Access control: only allow purging scopes this agent can access
+          if (!context.scopeManager.isAccessible(scope, agentId)) {
+            return {
+              content: [
+                {
+                  type: "text",
+                  text: `Access denied: scope "${scope}" is not accessible by agent "${agentId}".`,
+                },
+              ],
+              details: {
+                error: "scope_access_denied",
+                requestedScope: scope,
+                agentId,
+              },
+            };
+          }
+
+          try {
+            const deletedCount = await context.store.bulkDelete([scope]);
+            return {
+              content: [
+                {
+                  type: "text",
+                  text: `Purged scope "${scope}": ${deletedCount} memor${deletedCount === 1 ? "y" : "ies"} deleted.`,
+                },
+              ],
+              details: {
+                scope,
+                deletedCount,
+              },
+            };
+          } catch (error) {
+            return {
+              content: [
+                {
+                  type: "text",
+                  text: `Failed to purge scope "${scope}": ${error instanceof Error ? error.message : String(error)}`,
+                },
+              ],
+              details: { error: "purge_failed", message: String(error) },
+            };
+          }
+        },
+      };
+    },
+    { name: "memory_purge_scope" },
+  );
+}
+
 // ============================================================================
 // Tool Registration Helper
 // ============================================================================
@@ -1220,6 +1321,7 @@ export function registerAllMemoryTools(
   if (options.enableManagementTools) {
     registerMemoryStatsTool(api, context);
     registerMemoryListTool(api, context);
+    registerMemoryPurgeScopeTool(api, context);
   }
   if (options.enableSelfImprovementTools !== false) {
     registerSelfImprovementLogTool(api, context);