@@ -0,0 +1,20 @@
+---
+'@object-ui/react': patch
+'@object-ui/components': patch
+'@object-ui/app-shell': patch
+---
+
+fix(react,components,app-shell): a delegated admin's out-of-scope save shows the server's reason instead of the fixed no-permission line
+
+Clause-②: yes (widening: `@object-ui/react` exports a new `delegationScopeMessage`)
+Metadata-protocol: none
+
+When a delegated administrator saved something outside their own scope, the server answered `403 DELEGATION_SCOPE_VIOLATION` with the boundary that refused it (a business unit outside the delegated subtree, a permission set not in the scope's allowlist, a target user outside the subtree). The console read every 403 as a plain denial, so the toast and the in-form banner said only "You don't have permission to save this record."
+
+- **`@object-ui/react`.** New `delegationScopeMessage(err)`: the server's reason, without the `[Security] ` machine prefix, when the error's code (`code` or `details.code`) is `DELEGATION_SCOPE_VIOLATION`; `null` for everything else. It is read before `isPermissionError`, which still answers true for any 403.
+- **`@object-ui/components`.** The record form's toast and banner show that reason. A producer-marked `userMessage` still comes first.
+- **`@object-ui/app-shell`.** A flow run whose write node met the same refusal (`innerRefusal`) shows the same reason.
+
+Every other denial is unchanged: `PERMISSION_DENIED`, `FORBIDDEN`, a bare 403 and a row-level-security refusal still show the fixed localized line and never the server's text.
+
+What to do: nothing.
@@ -696,6 +696,25 @@ describe('interpretFlowResponse — a refusal met inside the run, by the record-
         expect((zh as { error: string }).error).not.toContain('crm_account');
     });
 
+    // objectstack#26059 Q3: a delegated admin's out-of-scope write is the one
+    // denial whose reason is shown; it describes only the caller's own scope.
+    it('a delegated-admin scope refusal shows the server reason, not the fixed permission line', () => {
+        const SCOPE_REASON =
+            "Outside your delegated scope: delegated 'create' on sys_user_position rejected — business unit 'bu_west' is outside the delegated subtree (scope from 'regional_admin').";
+        const SCOPE = { code: 'DELEGATION_SCOPE_VIOLATION', message: `[Security] ${SCOPE_REASON}` } as const;
+
+        expect(failed400(flowFailed({ innerRefusal: SCOPE }))).toEqual({
+            kind: 'failed', error: SCOPE_REASON, retryable: false,
+        });
+        const on200 = interpretFlowResponse(ok, {
+            success: true,
+            data: { success: false, status: 'failed', error: RAW_ERROR, innerRefusal: SCOPE },
+        }, 'Flow "assign"');
+        expect(on200).toMatchObject({ kind: 'failed', error: SCOPE_REASON });
+        // Control: a plain denial on the same path still reads the fixed line.
+        expect(failed400(flowFailed({ innerRefusal: DENIED }))).toMatchObject({ error: builtInLocales.en.form.noPermissionToSave });
+    });
+
     it('a producer-marked userMessage wins over the inner refusal, verbatim', () => {
         expect(failed400(flowFailed({ innerRefusal: UNIQUE }, USER_TEXT))).toMatchObject({ error: USER_TEXT });
         expect(failed400(flowFailed({ innerRefusal: DENIED }, USER_TEXT))).toMatchObject({ error: USER_TEXT });
 
@@ -214,7 +214,7 @@
 import { actionCopySource, actionErrorDetail } from '@object-ui/core';
 import type { ActionResult } from '@object-ui/core';
 import { getLoadedBuiltInLocales } from '@object-ui/i18n';
-import { declaredUserMessage, isPermissionError } from '@object-ui/react';
+import { declaredUserMessage, delegationScopeMessage, isPermissionError } from '@object-ui/react';
 import { errorCodeIs } from '@object-ui/types';
 import type { AutomationResult } from '@objectstack/spec/contracts';
 import { translateFlow, type TranslationBundle } from '@objectstack/spec/system';
@@ -368,7 +368,9 @@ function permissionDeniedLine(locale: string | undefined): string {
  * The inner refusal is rendered exactly as the record form renders the same
  * refusal on a save: a permission denial (`isPermissionError`) becomes the
  * form's localized permission line instead of server prose (objectstack#3821),
- * anything else reads its own sentence. `message` stays the last rung, so a
+ * anything else reads its own sentence. A delegated-admin scope refusal
+ * (`DELEGATION_SCOPE_VIOLATION`) reads its own reason, asked before the
+ * permission check exactly as the form asks it (objectstack#26059, Q3). `message` stays the last rung, so a
  * run that met no refusal still says something, never nothing.
  */
 function flowFailureMessage(failure: FlowFailureCarriers, message: string, copy: FlowCopyLocale | undefined): string {
@@ -378,6 +380,8 @@ function flowFailureMessage(failure: FlowFailureCarriers, message: string, copy:
     const inner = failure.innerRefusal as { code?: unknown; message?: unknown } | null | undefined;
     if (inner && typeof inner === 'object' && typeof inner.code === 'string') {
         const refusal = { code: inner.code, message: typeof inner.message === 'string' ? inner.message : '' };
+        const scopeReason = delegationScopeMessage(refusal);
+        if (scopeReason) return scopeReason;
         if (isPermissionError(refusal)) return permissionDeniedLine(copy?.locale);
         if (refusal.message.trim()) return refusal.message;
     }
 
@@ -160,3 +160,53 @@ describe('a producer-marked refusal reaches the user', () => {
     expect(await screen.findByText(/title must be unique/i)).toBeInTheDocument();
   });
 });
+
+/**
+ * objectstack#26059 Q3 (child #26190) — a delegated administrator who saves
+ * outside their own scope is told which boundary refused it.
+ *
+ * `403 DELEGATION_SCOPE_VIOLATION` is the one denial whose server reason is
+ * shown: it describes only the caller's own delegated scope. Every other denial
+ * keeps the fixed line (objectstack#24914 B′, unchanged), which the plain-403
+ * control below holds.
+ */
+describe('a delegated-admin scope refusal shows the server reason', () => {
+  const REASON =
+    "Outside your delegated scope: delegated 'update' on sys_user_position rejected — business unit 'bu_west' is outside the delegated subtree (scope from 'regional_admin').";
+
+  beforeEach(() => {
+    vi.spyOn(console, 'warn').mockImplementation(() => {});
+  });
+
+  function scopeRefusal() {
+    // The shape `@objectstack/client` hands the form for a 403: the server's
+    // message on `message`, the semantic code on `code`, the status on
+    // `httpStatus`.
+    return Object.assign(new Error(`[Security] ${REASON}`), {
+      code: 'DELEGATION_SCOPE_VIOLATION',
+      httpStatus: 403,
+    });
+  }
+
+  it("renders the server's reason, without the machine prefix, instead of the fixed line", async () => {
+    const { container } = renderForm(async () => { throw scopeRefusal(); });
+    fireEvent.click(screen.getByRole("button", { name: /submit/i }));
+
+    expect(await screen.findByText(REASON)).toBeInTheDocument();
+    expect(screen.queryByText(/permission to save/i)).not.toBeInTheDocument();
+    expect(container.textContent).not.toMatch(/\[Security\]/);
+  });
+
+  it('CONTROL: a plain 403 PERMISSION_DENIED keeps the fixed line and withholds its text', async () => {
+    const { container } = renderForm(async () => {
+      throw Object.assign(
+        new Error("[Security] Access denied: delegated 'update' on sys_user_position rejected — no delegated scope covers this write."),
+        { code: 'PERMISSION_DENIED', httpStatus: 403 },
+      );
+    });
+    fireEvent.click(screen.getByRole("button", { name: /submit/i }));
+
+    expect(await screen.findByText(/permission to save/i)).toBeInTheDocument();
+    expect(container.textContent).not.toMatch(/sys_user_position/);
+  });
+});
@@ -42,7 +42,7 @@ import { FullscreenEditor } from '../../custom/fullscreen-editor';
 import { CharacterCount } from '../../custom/character-count';
 import { cn } from '../../lib/utils';
 import React from 'react';
-import { SchemaRendererContext, usePredicateScope, isPermissionError, extractWriteErrorMessage, extractFieldErrors, declaredUserMessage } from '@object-ui/react';
+import { SchemaRendererContext, usePredicateScope, isPermissionError, extractWriteErrorMessage, extractFieldErrors, declaredUserMessage, delegationScopeMessage } from '@object-ui/react';
 import { createSafeTranslation } from '@object-ui/i18n';
 
 /**
@@ -3048,8 +3048,15 @@ ComponentRegistry.register('form',
         // construction rather than by us guessing what a 403 body contains.
         // Status-agnostic on purpose: 403 is where this was reported
         // (objectui#5210), not a fence the contract draws.
+        // A delegated administrator's out-of-scope write (`403
+        // DELEGATION_SCOPE_VIOLATION`) is the one denial whose reason is shown:
+        // it describes only the caller's own scope, and it tells them which
+        // boundary to fix (objectstack#26059, Q3). It is read before
+        // `isPermissionError`, which answers true for any 403; every other
+        // denial keeps the fixed line (objectstack#24914 B′).
         const errorMessage =
           declaredUserMessage(error) ??
+          delegationScopeMessage(error) ??
           (isPermissionError(error)
             ? t('form.noPermissionToSave')
             : extractWriteErrorMessage(error) ?? t('form.submitFailed'));
 
@@ -84,7 +84,7 @@ export type { PredicateGateKind } from './utils/visibilityDiagnostic.js';
 
 // Write-error surfacing utilities (shared by drag-write plugins so a failed
 // PATCH — e.g. an RLS 403 — is never silently swallowed).
-export { extractWriteErrorMessage, isPermissionError, extractFieldErrors, classifyLoadError, declaredUserMessage } from './utils/error-message.js';
+export { extractWriteErrorMessage, isPermissionError, extractFieldErrors, classifyLoadError, declaredUserMessage, delegationScopeMessage } from './utils/error-message.js';
 export type { WriteFieldError, LoadErrorKind } from './utils/error-message.js';
 
 // Built-in i18n support
 
@@ -10,7 +10,7 @@ import { describe, it, expect } from 'vitest';
 
 import { ApiErrorSchema } from '@objectstack/spec/api';
 
-import { extractFieldErrors, classifyLoadError, declaredUserMessage } from './error-message';
+import { extractFieldErrors, classifyLoadError, declaredUserMessage, delegationScopeMessage, isPermissionError } from './error-message';
 
 describe('extractFieldErrors', () => {
   // The wire shape the server actually sends: `@objectstack/rest` serves a
@@ -250,3 +250,44 @@ describe('declaredUserMessage', () => {
     expect(declaredUserMessage(parsedUnmarked)).toBeNull();
   });
 });
+
+// objectstack#26059 Q3: the one denial whose server reason a surface shows.
+describe('delegationScopeMessage', () => {
+  const REASON =
+    "Outside your delegated scope: delegated 'update' on sys_user_permission_set rejected — permission set 'finance_admin' is not in the scope's allowlist (scope from 'regional_admin').";
+
+  it("answers the server's reason, without the machine prefix, for a 403 DELEGATION_SCOPE_VIOLATION", () => {
+    const err = Object.assign(new Error(`[Security] ${REASON}`), {
+      code: 'DELEGATION_SCOPE_VIOLATION',
+      httpStatus: 403,
+    });
+    expect(delegationScopeMessage(err)).toBe(REASON);
+    // The reason it must be asked first: the permission predicate claims it too.
+    expect(isPermissionError(err)).toBe(true);
+  });
+
+  it('reads the code from `details` too, the pair isPermissionError reads', () => {
+    const err = Object.assign(new Error(`[Security] ${REASON}`), {
+      httpStatus: 403,
+      details: { code: 'DELEGATION_SCOPE_VIOLATION' },
+    });
+    expect(delegationScopeMessage(err)).toBe(REASON);
+  });
+
+  it('CONTROL: every other denial answers null, so its text stays withheld', () => {
+    const denied = (code: string | undefined) =>
+      Object.assign(new Error("[Security] Access denied: delegated 'update' on sys_user_position rejected — no scope."), {
+        code,
+        httpStatus: 403,
+      });
+    expect(delegationScopeMessage(denied('PERMISSION_DENIED'))).toBeNull();
+    expect(delegationScopeMessage(denied('FORBIDDEN'))).toBeNull();
+    expect(delegationScopeMessage(denied(undefined))).toBeNull();
+    expect(delegationScopeMessage(new Error('row-level security policy violation'))).toBeNull();
+    expect(delegationScopeMessage(null)).toBeNull();
+  });
+
+  it('answers null for a scope refusal with no usable text, so the caller still says something', () => {
+    expect(delegationScopeMessage({ code: 'DELEGATION_SCOPE_VIOLATION', httpStatus: 403, message: '' })).toBeNull();
+  });
+});
@@ -22,6 +22,7 @@
  */
 
 import { isApiAccessDeniedError } from '@object-ui/core';
+import { errorCodeIs } from '@object-ui/types';
 import type { ApiError } from '@objectstack/spec/api';
 
 /**
@@ -136,6 +137,43 @@ export function declaredUserMessage(err: unknown): string | null {
   return null;
 }
 
+/**
+ * The ADR-0112 code a delegated administrator's write answers when it falls
+ * outside the caller's OWN `adminScope` (the ledger row registered under
+ * `@objectstack/plugin-security`, thrown as `DelegationScopeViolationError`).
+ */
+const DELEGATION_SCOPE_VIOLATION = 'DELEGATION_SCOPE_VIOLATION';
+
+/**
+ * The server's reason for a delegated-admin scope refusal, or `null` when the
+ * refusal is anything else.
+ *
+ * A `403 DELEGATION_SCOPE_VIOLATION` names which boundary of the caller's own
+ * delegated scope refused the write (a business unit outside the delegated
+ * subtree, a permission set outside the allowlist, a target user outside the
+ * subtree). That text describes only the caller's own scope, so it is safe to
+ * show, and it tells the delegate what to fix (ruling on objectstack#26059, Q3).
+ * Every other denial stays opaque: `PERMISSION_DENIED`, `FORBIDDEN`, a bare 403
+ * or a row-level-security refusal answers `null` here, and callers keep their
+ * fixed localized line (ruling B′ on objectstack#24914, unchanged).
+ *
+ * Callers must ask this BEFORE {@link isPermissionError}: that predicate answers
+ * true for any 403, so a scope refusal read after it is flattened into the
+ * plain denial. The code is read from the same pair {@link isPermissionError}
+ * reads (`code`, then `details.code`); the text is
+ * {@link extractWriteErrorMessage}'s, without the `[Security] ` machine prefix.
+ * A scope refusal that carries no usable text answers `null`, so the caller
+ * still says something.
+ */
+export function delegationScopeMessage(err: unknown): string | null {
+  if (!err || typeof err !== 'object') return null;
+  const details = (err as { details?: unknown }).details;
+  if (!errorCodeIs(err, DELEGATION_SCOPE_VIOLATION) && !errorCodeIs(details, DELEGATION_SCOPE_VIOLATION)) {
+    return null;
+  }
+  return extractWriteErrorMessage(err);
+}
+
 /** One field the server rejected, normalised for `form.setError`. */
 export interface WriteFieldError {
   /** Field name, matching the form control's `name`. */
@@ -198,6 +236,10 @@ export function extractFieldErrors(err: unknown): WriteFieldError[] | null {
  * `PERMISSION_DENIED` / `FORBIDDEN` / a row-level-security denial). Lets a
  * caller show a friendly "you don't have permission" toast rather than dumping
  * the raw server text.
+ *
+ * A delegated-admin scope refusal is a 403 too, so this answers true for it:
+ * a caller that shows that refusal's reason asks
+ * {@link delegationScopeMessage} first.
  */
 export function isPermissionError(err: unknown): boolean {
   const e = err as Record<string, any> | null | undefined;