diff --git a/apps/desktop/src/main/__tests__/main-startup-lifetime.test.ts b/apps/desktop/src/main/__tests__/main-startup-lifetime.test.ts
index cb7b5d0a57..1b23ca1166 100644
--- a/apps/desktop/src/main/__tests__/main-startup-lifetime.test.ts
+++ b/apps/desktop/src/main/__tests__/main-startup-lifetime.test.ts
@@ -88,6 +88,31 @@ test('resolves persisted locale before first post-settings recovery prompt', ()
   assert.doesNotMatch(defaultHostRecovery, /resolveSystemUiLocale/u);
 });
 
+test('lets the Runtime Host migrate its State Root before Desktop opens shared tables', () => {
+  const hostStart = bootSource.indexOf(
+    'runtimeHostManager = await startDesktopRuntimeHostWithRecovery',
+  );
+  const workBoardOpen = bootSource.indexOf(
+    'store: createWorkBoardStore(workspaceRoot',
+  );
+  const sessionCopyOpen = bootSource.indexOf(
+    'createSessionCopyCleanupAuthority({',
+  );
+
+  assert.notEqual(hostStart, -1);
+  assert.notEqual(workBoardOpen, -1);
+  assert.notEqual(sessionCopyOpen, -1);
+  assert.ok(hostStart < workBoardOpen);
+  assert.match(
+    bootSource.slice(workBoardOpen, bootSource.indexOf('});', workBoardOpen)),
+    /schemaMigration: 'require_current'/u,
+  );
+  assert.match(
+    bootSource.slice(sessionCopyOpen, bootSource.indexOf('}),', sessionCopyOpen)),
+    /schemaMigration: 'require_current'/u,
+  );
+});
+
 test('routes the first-paint IPC only to the active Renderer recovery listener', () => {
   const ipcHandlerStart = appIpcSource.indexOf(
     "targetIpc.handle('window:notifyRendererReady'",
diff --git a/apps/desktop/src/main/runtime-host-boot.ts b/apps/desktop/src/main/runtime-host-boot.ts
index 608ebfd96c..20cbacff8d 100644
--- a/apps/desktop/src/main/runtime-host-boot.ts
+++ b/apps/desktop/src/main/runtime-host-boot.ts
@@ -442,7 +442,6 @@ resolveBrowserDialogAppearance = async () => {
   }
 };
 const mcpConfigStore = createMcpConfigStore(workspaceRoot);
-const workBoardStore = createWorkBoardStore(workspaceRoot);
 const mcpManager = new McpClientManager({
   clientName: "maka-desktop",
   clientVersion: app.getVersion(),
@@ -953,12 +952,6 @@ mcpManager.onChange(() => {
 
 registerPersistentClientIpc();
 registerPetPackIpc({ ipcMain, workspaceRoot, mainWindowController, settingsStore });
-const workBoardIpc = registerWorkBoardIpc({
-  ipcMain,
-  workspaceRoot,
-  mainWindowController,
-  store: workBoardStore,
-});
 const browserIpc = registerBrowserIpc({
   mainWindowController,
   isHostActive: (scope) => runtimeHostManager?.ownsScope(scope) === true,
@@ -1112,6 +1105,7 @@ const startLocalRuntimeHostManager = () => startRuntimeHostDesktopManager(
         removeSession,
         resumeSessionCopy,
         processId: sessionCopyOwnerProcessId,
+        databaseOptions: { schemaMigration: 'require_current' },
       }),
     renderer: mainWindowController,
     onError: (error) =>
@@ -1288,6 +1282,15 @@ runtimeHostManager = await startDesktopRuntimeHostWithRecovery({
   }
   throw error;
 });
+// Runtime Host is the only schema-migration authority for its State Root.
+// Work Board remains a Desktop-owned table, but it opens only after the Host is
+// ready and verifies the schema instead of changing it behind a resident Host.
+const workBoardIpc = registerWorkBoardIpc({
+  ipcMain,
+  workspaceRoot,
+  mainWindowController,
+  store: createWorkBoardStore(workspaceRoot, { schemaMigration: 'require_current' }),
+});
 wireLifecycle();
 runtimeHostManager.setDefaultProfile(runtimeHostStartup.preferences.defaultProfileId);
 await guestSessionMountService.start().catch((error: unknown) => {
diff --git a/packages/runtime-host/src/protocol/index.ts b/packages/runtime-host/src/protocol/index.ts
index d5a69a4d1e..b929c378be 100644
--- a/packages/runtime-host/src/protocol/index.ts
+++ b/packages/runtime-host/src/protocol/index.ts
@@ -100,7 +100,12 @@ export const RUNTIME_HOST_REGISTRATION_SCHEMA_VERSION = 1 as const;
 export const RUNTIME_HOST_PROTOCOL_VERSION = 0 as const;
 // Increment when the same protocol version no longer guarantees safe Client-Host
 // interoperability. Mismatches are rejected before domain commands are admitted.
-export const RUNTIME_HOST_COMPATIBILITY_EPOCH = 109 as const;
+export const RUNTIME_HOST_COMPATIBILITY_EPOCH = 110 as const;
+// 110: Runtime Host is the sole schema-migration authority for its State Root.
+// Epoch 109 Desktop builds could migrate the event-only AgentRun schema while
+// an older service Host still held the root, leaving that Host querying a
+// removed column. Reject the affected mixed generation before either process
+// admits domain work; the installation owner can then replace the Host.
 // 109: accepted Client Capability invocations may carry one bounded nested form
 // Interaction request/result round trip.
 // 108: Session Interaction snapshots, forwarded Runtime events, and Agent Graph
diff --git a/packages/storage/src/__tests__/operational-state-store.test.ts b/packages/storage/src/__tests__/operational-state-store.test.ts
index bea433ada7..11b8bb9ea6 100644
--- a/packages/storage/src/__tests__/operational-state-store.test.ts
+++ b/packages/storage/src/__tests__/operational-state-store.test.ts
@@ -24,7 +24,10 @@ import { join } from 'node:path';
 import { DatabaseSync } from 'node:sqlite';
 import { test } from 'node:test';
 import type { SessionHeader } from '@maka/core/session';
-import { acquireOperationalStateDatabase } from '../operational-state-store.js';
+import {
+  acquireOperationalStateDatabase,
+  OperationalStateMigrationBlockedError,
+} from '../operational-state-store.js';
 import { SQLITE_RUNTIME_SCHEMA_VERSION } from '../sqlite-runtime-schema.js';
 import { SQLITE_SESSION_METADATA_SCHEMA_VERSION } from '../sqlite-session-metadata-schema.js';
 import { SQLITE_USAGE_SCHEMA_VERSION } from '../sqlite-usage-schema.js';
@@ -101,6 +104,67 @@ test('atomically reapplies current owner schema without republishing its registr
   }
 });
 
+test('a non-owner rejects an older schema without migrating it behind the Runtime Host', async () => {
+  const root = await mkdtemp(join(tmpdir(), 'maka-operational-non-owner-'));
+  const databasePath = join(root, 'runtime.sqlite');
+  try {
+    acquireOperationalStateDatabase(root).close();
+    const older = new DatabaseSync(databasePath);
+    older.exec(`
+      ALTER TABLE core_agent_runs ADD COLUMN record_json TEXT;
+      UPDATE operational_schema_migrations
+      SET version = 6
+      WHERE scope = 'core_execution';
+    `);
+    older.close();
+
+    assert.throws(
+      () =>
+        acquireOperationalStateDatabase(root, {
+          schemaMigration: 'require_current',
+        }),
+      (error: unknown) =>
+        error instanceof OperationalStateMigrationBlockedError &&
+        /requires migration by its Runtime Host/u.test(error.message),
+    );
+
+    const preserved = new DatabaseSync(databasePath, { readOnly: true });
+    try {
+      const columns = preserved.prepare('PRAGMA table_info(core_agent_runs)').all() as Array<{
+        name: string;
+      }>;
+      assert.ok(columns.some(({ name }) => name === 'record_json'));
+      assert.equal(
+        (
+          preserved
+            .prepare(
+              "SELECT version FROM operational_schema_migrations WHERE scope = 'core_execution'",
+            )
+            .get() as { version: number }
+        ).version,
+        6,
+      );
+    } finally {
+      preserved.close();
+    }
+
+    const hostOwned = acquireOperationalStateDatabase(root);
+    try {
+      const columns = hostOwned.database
+        .prepare('PRAGMA table_info(core_agent_runs)')
+        .all() as Array<{ name: string }>;
+      assert.equal(
+        columns.some(({ name }) => name === 'record_json'),
+        false,
+      );
+    } finally {
+      hostOwned.close();
+    }
+  } finally {
+    await rm(root, { recursive: true, force: true });
+  }
+});
+
 test('retires completed released migration metadata during schema convergence', async () => {
   const root = await mkdtemp(join(tmpdir(), 'maka-operational-cutover-retirement-'));
   const databasePath = join(root, 'runtime.sqlite');
diff --git a/packages/storage/src/operational-state-store.ts b/packages/storage/src/operational-state-store.ts
index 5f2772a680..63faeba31c 100644
--- a/packages/storage/src/operational-state-store.ts
+++ b/packages/storage/src/operational-state-store.ts
@@ -142,6 +142,12 @@ const owners = new Map<string, OperationalStateDatabaseOwner>();
 
 export interface OperationalStateDatabaseOptions {
   now?: () => number;
+  /**
+   * `migrate` is reserved for the process that owns the State Root. A
+   * secondary process may use `require_current` to share current tables, but
+   * it must never rewrite the schema underneath that owner.
+   */
+  schemaMigration?: 'migrate' | 'require_current';
 }
 
 export class OperationalStateMigrationBlockedError extends Error {
@@ -193,13 +199,22 @@ class OperationalStateDatabaseOwner {
     readonly databasePath: string,
     options: OperationalStateDatabaseOptions,
   ) {
+    if (options.schemaMigration === 'require_current' && !existsSync(databasePath)) {
+      throw new OperationalStateMigrationBlockedError(
+        new Error('Operational state has not been initialized by its Runtime Host'),
+      );
+    }
     mkdirSync(dirname(databasePath), { recursive: true });
     const Database = loadDatabaseSync();
     this.database = new Database(databasePath);
     try {
       configureSqliteRuntimeLockWait(this.database);
       this.database.exec('PRAGMA foreign_keys = ON');
-      inspectAndMigrateOperationalState(this.database, options.now ?? Date.now);
+      if (options.schemaMigration === 'require_current') {
+        requireCurrentOperationalState(this.database);
+      } else {
+        inspectAndMigrateOperationalState(this.database, options.now ?? Date.now);
+      }
       configureSqliteRuntimeDatabase(this.database);
     } catch (error) {
       this.database.close();
@@ -272,6 +287,18 @@ class OperationalStateDatabaseOwner {
   }
 }
 
+function requireCurrentOperationalState(database: DatabaseSync): void {
+  try {
+    const inspection = inspectOperationalStateSchema(database);
+    if (inspection.status === 'current' && isCurrentOperationalTargetSchema(database)) return;
+    throw new Error('Operational state requires migration by its Runtime Host');
+  } catch (error) {
+    if (isSqliteEnvironmentError(error)) throw error;
+    if (error instanceof OperationalStateMigrationBlockedError) throw error;
+    throw new OperationalStateMigrationBlockedError(error);
+  }
+}
+
 function inspectAndMigrateOperationalState(database: DatabaseSync, now: () => number): void {
   try {
     const inspection = inspectOperationalStateSchema(database);
diff --git a/packages/storage/src/session-copy-cleanup.ts b/packages/storage/src/session-copy-cleanup.ts
index 64b11143a6..a1cf6dd62b 100644
--- a/packages/storage/src/session-copy-cleanup.ts
+++ b/packages/storage/src/session-copy-cleanup.ts
@@ -18,7 +18,10 @@
  */
 
 import { randomUUID } from 'node:crypto';
-import { acquireOperationalStateDatabase } from './operational-state-store.js';
+import {
+  acquireOperationalStateDatabase,
+  type OperationalStateDatabaseOptions,
+} from './operational-state-store.js';
 import {
   isProcessLifetimeOwnerReference,
   type ProcessLifetimeOwner,
@@ -84,9 +87,10 @@ export function createSessionCopyCleanupAuthority(input: {
   processId?: string;
   isOwnerProcessActive?: (ownerProcessId: string) => boolean | Promise<boolean>;
   processLifetimeOwner?: ProcessLifetimeOwner;
+  databaseOptions?: OperationalStateDatabaseOptions;
 }): SessionCopyCleanupAuthority {
   return new SessionCopyCleanupAuthorityImpl(
-    new SqliteSessionCopyCleanupStore(input.workspaceRoot),
+    new SqliteSessionCopyCleanupStore(input.workspaceRoot, input.databaseOptions),
     input.removeSession,
     input.resumeSessionCopy,
     input.processId ?? randomUUID(),
@@ -304,7 +308,10 @@ class SessionCopyCleanupAuthorityImpl implements SessionCopyCleanupAuthority {
 }
 
 class SqliteSessionCopyCleanupStore implements SessionCopyCleanupStore {
-  constructor(private readonly workspaceRoot: string) {}
+  constructor(
+    private readonly workspaceRoot: string,
+    private readonly databaseOptions: OperationalStateDatabaseOptions = {},
+  ) {}
 
   async list(): Promise<PersistedSessionCopyLease[]> {
     return this.withDatabase('read', (database) =>
@@ -432,7 +439,7 @@ class SqliteSessionCopyCleanupStore implements SessionCopyCleanupStore {
     mode: 'read' | 'write',
     operation: (database: import('node:sqlite').DatabaseSync) => T,
   ): T {
-    const lease = acquireOperationalStateDatabase(this.workspaceRoot);
+    const lease = acquireOperationalStateDatabase(this.workspaceRoot, this.databaseOptions);
     try {
       return lease.transaction(mode, () => operation(lease.database));
     } finally {
diff --git a/packages/storage/src/work-board-store.ts b/packages/storage/src/work-board-store.ts
index 5d2970a16f..75b2fd1443 100644
--- a/packages/storage/src/work-board-store.ts
+++ b/packages/storage/src/work-board-store.ts
@@ -39,6 +39,7 @@ import {
 } from './work-board-list-query.js';
 import {
   acquireOperationalStateDatabase,
+  type OperationalStateDatabaseOptions,
   type OperationalStateDatabaseLease,
 } from './operational-state-store.js';
 import { chainWrite } from './write-queue.js';
@@ -70,8 +71,11 @@ export interface WorkBoardStore {
   close(): void;
 }
 
-export function createWorkBoardStore(workspaceRoot: string): WorkBoardStore {
-  return new SqliteWorkBoardStore(workspaceRoot);
+export function createWorkBoardStore(
+  workspaceRoot: string,
+  databaseOptions: OperationalStateDatabaseOptions = {},
+): WorkBoardStore {
+  return new SqliteWorkBoardStore(workspaceRoot, databaseOptions);
 }
 
 interface WorkBoardRow {
@@ -89,8 +93,8 @@ class SqliteWorkBoardStore implements WorkBoardStore {
   readonly #lease: OperationalStateDatabaseLease;
   private readonly writeQueues = new Map<string, Promise<void>>();
 
-  constructor(workspaceRoot: string) {
-    this.#lease = acquireOperationalStateDatabase(resolve(workspaceRoot));
+  constructor(workspaceRoot: string, databaseOptions: OperationalStateDatabaseOptions) {
+    this.#lease = acquireOperationalStateDatabase(resolve(workspaceRoot), databaseOptions);
   }
 
   close(): void {