diff --git a/src/batch-policy.ts b/src/batch-policy.ts
index 651c892de..3489d512c 100644
--- a/src/batch-policy.ts
+++ b/src/batch-policy.ts
@@ -1,4 +1,3 @@
-import { PUBLIC_COMMANDS } from './command-catalog.ts';
 import { deriveStructuredBatchCommandNames } from './core/command-descriptor/derive.ts';
 import { commandDescriptors } from './core/command-descriptor/registry.ts';
 import { AppError } from './utils/errors.ts';
@@ -6,67 +5,27 @@ import { AppError } from './utils/errors.ts';
 /**
  * The exact set of command names exposed through `batch`, as a narrow union.
  *
- * This type is kept HAND-AUTHORED on purpose (ADR-0008, Phase 1 step 4): the
- * runtime allowlist below is now derived from the command-descriptor registry,
- * but the registry types each `name` as `string`, so deriving the value yields
- * `string[]`. Re-deriving the type from that value would WIDEN this union to
- * `string` and silently widen its downstream consumers — most notably
- * `BatchCommandName` (re-exported from `command-surface.ts`) and the
- * `satisfies readonly DaemonCommandName[]` guard in `commands/batch/projection.ts`.
- * Keeping the union spelled out preserves those compile-time contracts. The
- * derived runtime value is proven to match this union, member-for-member, by
- * `core/command-descriptor/__tests__/parity.test.ts`.
+ * DERIVED from the command-descriptor registry (ADR-0008, Phase 1 step 7): the
+ * registry is now `as const` (#910), so each entry keeps its literal `name` and
+ * literal `batchable`. Extracting the entries whose `batchable` is `true` and
+ * indexing their `name` reconstructs this union from the same single source the
+ * runtime allowlist below is built from — no hand-maintained list to drift. The
+ * downstream contracts (`BatchCommandName`, re-exported from `command-surface.ts`,
+ * and the `satisfies readonly DaemonCommandName[]` guard in
+ * `commands/batch/projection.ts`) are still enforced by `tsc`.
  */
-export type StructuredBatchCommandName =
-  | (typeof PUBLIC_COMMANDS)['devices']
-  | (typeof PUBLIC_COMMANDS)['boot']
-  | (typeof PUBLIC_COMMANDS)['shutdown']
-  | (typeof PUBLIC_COMMANDS)['apps']
-  | (typeof PUBLIC_COMMANDS)['open']
-  | (typeof PUBLIC_COMMANDS)['close']
-  | (typeof PUBLIC_COMMANDS)['install']
-  | (typeof PUBLIC_COMMANDS)['reinstall']
-  | (typeof PUBLIC_COMMANDS)['installFromSource']
-  | (typeof PUBLIC_COMMANDS)['push']
-  | (typeof PUBLIC_COMMANDS)['triggerAppEvent']
-  | (typeof PUBLIC_COMMANDS)['snapshot']
-  | (typeof PUBLIC_COMMANDS)['screenshot']
-  | (typeof PUBLIC_COMMANDS)['diff']
-  | (typeof PUBLIC_COMMANDS)['wait']
-  | (typeof PUBLIC_COMMANDS)['alert']
-  | (typeof PUBLIC_COMMANDS)['settings']
-  | (typeof PUBLIC_COMMANDS)['click']
-  | (typeof PUBLIC_COMMANDS)['press']
-  | (typeof PUBLIC_COMMANDS)['longPress']
-  | (typeof PUBLIC_COMMANDS)['swipe']
-  | (typeof PUBLIC_COMMANDS)['focus']
-  | (typeof PUBLIC_COMMANDS)['type']
-  | (typeof PUBLIC_COMMANDS)['fill']
-  | (typeof PUBLIC_COMMANDS)['scroll']
-  | (typeof PUBLIC_COMMANDS)['get']
-  | (typeof PUBLIC_COMMANDS)['gesture']
-  | (typeof PUBLIC_COMMANDS)['is']
-  | (typeof PUBLIC_COMMANDS)['find']
-  | (typeof PUBLIC_COMMANDS)['perf']
-  | (typeof PUBLIC_COMMANDS)['logs']
-  | (typeof PUBLIC_COMMANDS)['network']
-  | (typeof PUBLIC_COMMANDS)['record']
-  | (typeof PUBLIC_COMMANDS)['trace']
-  | (typeof PUBLIC_COMMANDS)['test']
-  | (typeof PUBLIC_COMMANDS)['appState']
-  | (typeof PUBLIC_COMMANDS)['back']
-  | (typeof PUBLIC_COMMANDS)['home']
-  | (typeof PUBLIC_COMMANDS)['rotate']
-  | (typeof PUBLIC_COMMANDS)['appSwitcher']
-  | (typeof PUBLIC_COMMANDS)['keyboard']
-  | (typeof PUBLIC_COMMANDS)['clipboard']
-  | (typeof PUBLIC_COMMANDS)['reactNative'];
+export type StructuredBatchCommandName = Extract<
+  (typeof commandDescriptors)[number],
+  { batchable: true }
+>['name'];
 
 /**
  * The structured-batch allowlist, BUILT from the command-descriptor registry
- * (the `batchable` flag) rather than hand-maintained. The derived value is a
+ * (the `batchable` flag) rather than hand-maintained. {@link deriveStructuredBatchCommandNames}
+ * folds over the registry as `readonly CommandDescriptor[]`, so it returns
  * `string[]`; the cast re-applies the narrow {@link StructuredBatchCommandName}
- * union, whose membership equality with this value is asserted by the parity test.
+ * union (which derives from the same `batchable: true` entries). The parity test
+ * guards the wiring (the exported value equals the derived fold).
  */
 export const STRUCTURED_BATCH_COMMAND_NAMES: readonly StructuredBatchCommandName[] =
   deriveStructuredBatchCommandNames(commandDescriptors) as readonly StructuredBatchCommandName[];
diff --git a/src/core/command-descriptor/__tests__/parity.test.ts b/src/core/command-descriptor/__tests__/parity.test.ts
index 101f86d05..cf05288d1 100644
--- a/src/core/command-descriptor/__tests__/parity.test.ts
+++ b/src/core/command-descriptor/__tests__/parity.test.ts
@@ -1,9 +1,6 @@
 import assert from 'node:assert/strict';
 import { test } from 'vitest';
-import {
-  STRUCTURED_BATCH_COMMAND_NAMES,
-  type StructuredBatchCommandName,
-} from '../../../batch-policy.ts';
+import { STRUCTURED_BATCH_COMMAND_NAMES } from '../../../batch-policy.ts';
 import { PUBLIC_COMMANDS } from '../../../command-catalog.ts';
 import { BASE_COMMAND_CAPABILITY_MATRIX } from '../../capabilities.ts';
 import {
@@ -132,56 +129,6 @@ test('capability matrix holds its admission invariants', () => {
   }
 });
 
-// Exhaustive map over the StructuredBatchCommandName union. The compiler errors
-// if a union member is missing a key OR a non-member key is added, so its keys
-// ARE the union at type level — giving us a runtime handle on the (otherwise
-// hand-authored) union to compare against the derived allowlist.
-const STRUCTURED_BATCH_UNION_MEMBERS: Record<StructuredBatchCommandName, true> = {
-  [PUBLIC_COMMANDS.devices]: true,
-  [PUBLIC_COMMANDS.boot]: true,
-  [PUBLIC_COMMANDS.shutdown]: true,
-  [PUBLIC_COMMANDS.apps]: true,
-  [PUBLIC_COMMANDS.open]: true,
-  [PUBLIC_COMMANDS.close]: true,
-  [PUBLIC_COMMANDS.install]: true,
-  [PUBLIC_COMMANDS.reinstall]: true,
-  [PUBLIC_COMMANDS.installFromSource]: true,
-  [PUBLIC_COMMANDS.push]: true,
-  [PUBLIC_COMMANDS.triggerAppEvent]: true,
-  [PUBLIC_COMMANDS.snapshot]: true,
-  [PUBLIC_COMMANDS.screenshot]: true,
-  [PUBLIC_COMMANDS.diff]: true,
-  [PUBLIC_COMMANDS.wait]: true,
-  [PUBLIC_COMMANDS.alert]: true,
-  [PUBLIC_COMMANDS.settings]: true,
-  [PUBLIC_COMMANDS.click]: true,
-  [PUBLIC_COMMANDS.press]: true,
-  [PUBLIC_COMMANDS.longPress]: true,
-  [PUBLIC_COMMANDS.swipe]: true,
-  [PUBLIC_COMMANDS.focus]: true,
-  [PUBLIC_COMMANDS.type]: true,
-  [PUBLIC_COMMANDS.fill]: true,
-  [PUBLIC_COMMANDS.scroll]: true,
-  [PUBLIC_COMMANDS.get]: true,
-  [PUBLIC_COMMANDS.gesture]: true,
-  [PUBLIC_COMMANDS.is]: true,
-  [PUBLIC_COMMANDS.find]: true,
-  [PUBLIC_COMMANDS.perf]: true,
-  [PUBLIC_COMMANDS.logs]: true,
-  [PUBLIC_COMMANDS.network]: true,
-  [PUBLIC_COMMANDS.record]: true,
-  [PUBLIC_COMMANDS.trace]: true,
-  [PUBLIC_COMMANDS.test]: true,
-  [PUBLIC_COMMANDS.appState]: true,
-  [PUBLIC_COMMANDS.back]: true,
-  [PUBLIC_COMMANDS.home]: true,
-  [PUBLIC_COMMANDS.rotate]: true,
-  [PUBLIC_COMMANDS.appSwitcher]: true,
-  [PUBLIC_COMMANDS.keyboard]: true,
-  [PUBLIC_COMMANDS.clipboard]: true,
-  [PUBLIC_COMMANDS.reactNative]: true,
-};
-
 // Control-plane / non-batchable commands that must never enter the allowlist.
 const NON_BATCHABLE_COMMANDS = [
   PUBLIC_COMMANDS.batch,
@@ -195,29 +142,23 @@ const NON_BATCHABLE_COMMANDS = [
   'transform-gesture',
 ];
 
-test('structured-batch allowlist is built from descriptors and matches the kept union', () => {
+test('structured-batch allowlist is built from descriptors', () => {
   const derived = deriveStructuredBatchCommandNames(commandDescriptors);
 
   // No duplicates in the derived allowlist.
   assert.equal(new Set(derived).size, derived.length, 'no duplicate batchable names');
 
   // The exported allowlist is now BUILT from these derived descriptors, so it is
-  // the derived list (order included) — guards the wiring, not a tautology of
-  // membership.
+  // the derived list (order included) — guards the wiring. (The narrow
+  // StructuredBatchCommandName union now DERIVES from the same `batchable: true`
+  // entries via Extract, so an exhaustive-union membership check would be a
+  // tautology; `tsc` enforces the type, this guards the value.)
   assert.deepEqual(
     [...STRUCTURED_BATCH_COMMAND_NAMES],
     derived,
     'exported allowlist is built from the descriptors',
   );
 
-  // Membership equals the kept StructuredBatchCommandName union (proves the
-  // narrow type the consumers rely on did not drift from the runtime value).
-  assert.deepEqual(
-    [...new Set(derived)].sort(),
-    Object.keys(STRUCTURED_BATCH_UNION_MEMBERS).sort(),
-    'derived membership equals the kept union',
-  );
-
   // Every batchable command is a real public command (no internal/control name leaks in).
   const publicCommands = new Set<string>(Object.values(PUBLIC_COMMANDS));
   for (const name of derived) {