@@ -0,0 +1,15 @@
+---
+"@objectstack/plugin-auth": patch
+---
+
+fix(plugin-auth): the organization, invitation-placement and phone-OTP hook refusals carry their ADR-0112 codes
+
+Clause-②: no
+
+Eight refusals thrown from plugin-auth's better-auth hooks answered with `message` alone, so a client could only show or match English prose. Each now carries a `code` it can branch on, and keeps its HTTP status.
+
+- `POST /auth/organization/create`: the reserved `__global__` id or slug answers 400 `VALIDATION_ERROR`. Where the deployment's effective tenancy posture enforces no organization wall (`/auth/config` publishes `features.multiOrgEnabled: false`), creating an organization answers 403 `ORGANIZATION_CREATION_DISABLED`.
+- `POST /auth/organization/invite-member` with placement intent (`businessUnitId` and `positions`): with no delegated-administration runtime to authorize it, 403 `INVITE_PLACEMENT_UNSUPPORTED`; refused by the delegated-administration gate, 403 `INVITE_PLACEMENT_OUTSIDE_ISSUER_SCOPE`.
+- `POST /auth/organization/update` with a new slug: while the organization has an active environment (any environment that is neither archived nor failed), 403 `ORGANIZATION_SLUG_LOCKED_BY_ACTIVE_ENVIRONMENTS`. Its message no longer says environments "still reference" the organization or tells you to rename their hostnames: the guard reads no hostname, and archiving those environments is the remedy. When the guard's own read cannot answer, 503 `SERVICE_UNAVAILABLE`.
+- Phone OTP sends (`/auth/phone-number/send-otp`, `/auth/phone-number/request-password-reset`): the per-number limit and the deployment's daily SMS quota both answer 429 `RATE_LIMIT_EXCEEDED`. It is one code for both walls, so a caller still cannot tell which budget it hit. The body is better-auth's flat `code` and `message`, with no `Retry-After` header.
+- **One behaviour change:** a placement check that fails before the gate reaches a verdict (the issuer's grants could not be read from the store) now answers 503 `SERVICE_UNAVAILABLE`, not a 403 scope refusal carrying the store's message. No invitation is created either way.
@@ -738,8 +738,9 @@ have let them count the dependents; `dependentObject` is named either way. Treat
 #### `RATE_LIMIT_EXCEEDED`
 **HTTP Status:** 429  
 **Meaning:** Too many requests, rate limit exceeded  
-**Envelope:** nested — built by the inbound rate limiter, which sits **ahead of every
-route**, so it is never flat whichever family you were calling
+**Envelope:** nested from the inbound rate limiter, which sits **ahead of every
+route**, so its refusal is never flat whichever family you were calling. The phone-OTP
+send walls answer this code too, flat (see the end of `QUOTA_EXCEEDED` below)
 
 **Example:**
 ```json
@@ -835,10 +836,14 @@ Don't feed this 429 to a retry loop that only checks the status, such as the
 `RATE_LIMIT_EXCEEDED` example above. It has no `Retry-After` to wait on, and every
 retry before `resetAt` is refused again.
 
-Other quota enforcement answers with its own code rather than this one
-(the SMS daily quota answers `TOO_MANY_REQUESTS`). For request pacing, the code
-on the wire is `RATE_LIMIT_EXCEEDED` above, whose `Retry-After` header and
-`retryAfterSeconds` / `resetAt` details are what a client acts on.
+Other quota enforcement answers with a code other than this one. The phone-OTP send
+walls (`/auth/phone-number/send-otp` and `/auth/phone-number/request-password-reset`), a
+phone number's own limit and the deployment's daily SMS quota, both answer 429
+`RATE_LIMIT_EXCEEDED`: one code for both, so a caller cannot tell which budget it hit.
+That body is better-auth's flat `code` and `message`, with no `Retry-After` header and no
+`details`. At the inbound rate limiter, the code on the wire is `RATE_LIMIT_EXCEEDED`
+above, whose `Retry-After` header and `retryAfterSeconds` / `resetAt` details are what a
+client acts on.
 
 ### Server Errors
 
 
@@ -0,0 +1,244 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * [#24243, ADR-0112] Every `new APIError(` this package throws carries a `code`.
+ *
+ * better-auth serialises an `APIError` body as it is given. A body without a
+ * `code` reaches the caller as `message` alone, so a client (the console among
+ * them) can only show or pattern-match English prose, on doors where
+ * better-auth's own refusals carry codes. Eight throws in `auth-manager.ts`
+ * shipped that way, found by hand; this pin is the enumeration, so the next one
+ * cannot ship without a code. It is a test in this package, not a CI gate.
+ *
+ * It PARSES every non-test source file under `src/` and finds every
+ * `new APIError(...)`. A site passes when its body carries the code in one of
+ * two shapes, and is reported with its file and line otherwise:
+ *
+ *  1. an object literal with a top-level `code` property; or
+ *  2. a body destructured, in the same function, from the result of
+ *     `judgeHeldSession(...)`: the held-session judge's ADR-0112 envelope,
+ *     whose code sits under `error` (`platform-admin-gate.held-session.test.ts`
+ *     pins that body's shape).
+ *
+ * No body, a literal without `code`, a spread, or an identifier from anywhere
+ * else is a site this pin cannot read a code from, so it fails.
+ *
+ * It parses and does not type-check, so the code's VALUE is not judged here.
+ * Each stamp is a constant typed `RegisteredErrorCode` or `StandardErrorCode`,
+ * so `tsc` judges the value, and `check:error-code-provenance` judges whether a
+ * registered one is listed under this package.
+ *
+ * Two controls keep the walk honest:
+ *  - a textual count over the comment-free source (the TypeScript printer, with
+ *    comments removed) must equal the sites the walk found in each file, so a
+ *    constructor spelling the walk does not recognise cannot slip past it;
+ *  - the classifier must report each shape that shipped without a code and
+ *    accept each shape that carries one (the fixture battery below).
+ */
+
+import { describe, it, expect } from 'vitest';
+import { readdirSync, readFileSync } from 'node:fs';
+import { dirname, join, relative } from 'node:path';
+import { fileURLToPath } from 'node:url';
+import ts from 'typescript';
+
+const HERE = dirname(fileURLToPath(import.meta.url));
+
+interface ApiErrorSite {
+  readonly file: string;
+  readonly line: number;
+  /** `null` when the body carries a code; otherwise why this pin cannot read one. */
+  readonly missing: string | null;
+}
+
+const isTestFile = (name: string): boolean => /\.(test|spec)\.tsx?$/.test(name) || name.endsWith('.d.ts');
+
+function sourceFiles(dir: string): string[] {
+  const out: string[] = [];
+  for (const entry of readdirSync(dir, { withFileTypes: true })) {
+    const path = join(dir, entry.name);
+    if (entry.isDirectory()) out.push(...sourceFiles(path));
+    else if (/\.tsx?$/.test(entry.name) && !isTestFile(entry.name)) out.push(path);
+  }
+  return out.sort();
+}
+
+const isApiErrorCallee = (callee: ts.Expression): boolean =>
+  (ts.isIdentifier(callee) && callee.text === 'APIError') ||
+  (ts.isPropertyAccessExpression(callee) && callee.name.text === 'APIError');
+
+function propertyName(name: ts.PropertyName): string | undefined {
+  if (ts.isIdentifier(name) || ts.isStringLiteral(name)) return name.text;
+  return undefined;
+}
+
+function enclosingFunction(node: ts.Node): ts.Node | undefined {
+  for (let cur = node.parent; cur; cur = cur.parent) {
+    if (ts.isFunctionLike(cur)) return cur;
+  }
+  return undefined;
+}
+
+/** Every variable declaration inside `scope`, nested blocks included. */
+function declarationsIn(scope: ts.Node): ts.VariableDeclaration[] {
+  const found: ts.VariableDeclaration[] = [];
+  const visit = (node: ts.Node): void => {
+    if (ts.isVariableDeclaration(node)) found.push(node);
+    ts.forEachChild(node, visit);
+  };
+  visit(scope);
+  return found;
+}
+
+const unwrapAwait = (e: ts.Expression | undefined): ts.Expression | undefined =>
+  e && ts.isAwaitExpression(e) ? e.expression : e;
+
+/**
+ * Shape 2: `const { body } = held;` (or `{ body: X }`) where `held` is
+ * `judgeHeldSession(…)`'s result, both in the throw's own function.
+ */
+function isHeldSessionBody(body: ts.Identifier, site: ts.NewExpression): boolean {
+  const scope = enclosingFunction(site);
+  if (!scope) return false;
+  const decls = declarationsIn(scope);
+  const holders = decls
+    .filter((d) => ts.isObjectBindingPattern(d.name) && d.initializer && ts.isIdentifier(d.initializer))
+    .filter((d) =>
+      (d.name as ts.ObjectBindingPattern).elements.some((el) => {
+        const key = el.propertyName ? propertyName(el.propertyName) : ts.isIdentifier(el.name) ? el.name.text : undefined;
+        return key === 'body' && ts.isIdentifier(el.name) && el.name.text === body.text;
+      }),
+    )
+    .map((d) => (d.initializer as ts.Identifier).text);
+  return holders.some((holder) =>
+    decls.some((d) => {
+      if (!ts.isIdentifier(d.name) || d.name.text !== holder) return false;
+      const init = unwrapAwait(d.initializer);
+      return (
+        !!init && ts.isCallExpression(init) && ts.isIdentifier(init.expression) && init.expression.text === 'judgeHeldSession'
+      );
+    }),
+  );
+}
+
+function whyCodeless(site: ts.NewExpression, sf: ts.SourceFile): string | null {
+  const body = site.arguments?.[1];
+  if (!body) return 'it passes no body at all';
+  if (ts.isObjectLiteralExpression(body)) {
+    const carriesCode = body.properties.some(
+      (p) => (ts.isPropertyAssignment(p) || ts.isShorthandPropertyAssignment(p)) && propertyName(p.name) === 'code',
+    );
+    return carriesCode ? null : 'its body has no top-level `code` property';
+  }
+  if (ts.isIdentifier(body) && isHeldSessionBody(body, site)) return null;
+  return `its body is \`${body.getText(sf)}\`, which this pin cannot read a code from`;
+}
+
+/** Every `new APIError(…)` in one source text, each with its verdict. */
+function apiErrorSites(file: string, text: string): ApiErrorSite[] {
+  const sf = ts.createSourceFile(file, text, ts.ScriptTarget.Latest, true, ts.ScriptKind.TS);
+  const sites: ApiErrorSite[] = [];
+  const visit = (node: ts.Node): void => {
+    if (ts.isNewExpression(node) && isApiErrorCallee(node.expression)) {
+      sites.push({
+        file,
+        line: sf.getLineAndCharacterOfPosition(node.getStart(sf)).line + 1,
+        missing: whyCodeless(node, sf),
+      });
+    }
+    ts.forEachChild(node, visit);
+  };
+  visit(sf);
+  return sites;
+}
+
+/** The textual control: constructor calls counted in the source with its comments removed. */
+function textualCount(file: string, text: string): number {
+  const sf = ts.createSourceFile(file, text, ts.ScriptTarget.Latest, false, ts.ScriptKind.TS);
+  const printed = ts.createPrinter({ removeComments: true }).printFile(sf);
+  return printed.match(/\bnew\s+(?:[A-Za-z_$][\w$]*\s*\.\s*)*APIError\s*\(/g)?.length ?? 0;
+}
+
+describe('every new APIError( in plugin-auth/src carries an ADR-0112 code (#24243)', () => {
+  const files = sourceFiles(HERE);
+  const perFile = files.map((path) => {
+    const text = readFileSync(path, 'utf8');
+    const file = relative(HERE, path);
+    return { file, sites: apiErrorSites(file, text), textual: textualCount(file, text) };
+  });
+  const sites = perFile.flatMap((f) => f.sites);
+
+  it('the walk reaches the throws: a floor of sites and files, so a walk that reads nothing cannot pass', () => {
+    // Measured when this pin landed: 30 sites in 4 files (`auth-manager.ts`
+    // 24, `objectql-adapter.ts` 3, `impersonation-bearer-rotation.ts` 2,
+    // `admin-impersonate-endpoint.ts` 1). A floor, not an exact count, so a new
+    // throw does not have to edit this line; only losing them does.
+    expect(sites.length).toBeGreaterThanOrEqual(30);
+    expect(new Set(sites.map((s) => s.file)).size).toBeGreaterThanOrEqual(4);
+    expect(perFile.find((f) => f.file === 'auth-manager.ts')?.sites.length ?? 0).toBeGreaterThanOrEqual(24);
+  });
+
+  it('the textual control agrees with the walk in every file', () => {
+    const disagreements = perFile
+      .filter((f) => f.textual !== f.sites.length)
+      .map((f) => `${f.file}: ${f.textual} textual, ${f.sites.length} walked`);
+    expect(disagreements).toEqual([]);
+  });
+
+  it('no site throws a body without a code', () => {
+    const codeless = sites.filter((s) => s.missing !== null).map((s) => `${s.file}:${s.line}: ${s.missing}`);
+    expect(codeless).toEqual([]);
+  });
+});
+
+describe('the classifier, against the shapes it must tell apart', () => {
+  const verdicts = (body: string) => apiErrorSites('fixture.ts', body).map((s) => s.missing === null);
+
+  it('reports both shapes the eight code-less throws had (the card enumeration)', () => {
+    // As they stood before #24243: a status read off a constant with a
+    // message-only body (the SMS quota wall), and a status literal with a
+    // message-only body (the other seven).
+    const fixture = `
+      async function quota(message: string) { return new APIError(SMS_QUOTA_EXCEEDED_CODE, { message }); }
+      async function hook() {
+        throw new APIError('FORBIDDEN', { message: 'Creating additional organizations is disabled.' });
+      }
+      async function relayed(err: any) {
+        throw new APIError('FORBIDDEN', { message: err?.message ?? 'outside your scope' });
+      }`;
+    expect(verdicts(fixture)).toEqual([false, false, false]);
+  });
+
+  it('reports a site with no body, a spread with no code, and an identifier it cannot trace', () => {
+    const fixture = `
+      function a() { throw new APIError('FORBIDDEN'); }
+      function b(base: object) { throw new APIError('FORBIDDEN', { ...base }); }
+      function c(body: object) { throw new APIError('FORBIDDEN', body); }
+      function d() { const { body } = somethingElse(); throw new APIError('FORBIDDEN', body); }`;
+    expect(verdicts(fixture)).toEqual([false, false, false, false]);
+  });
+
+  it('accepts a literal or shorthand `code`, a string key, a member callee and the held-session relay', () => {
+    const fixture = `
+      function a() { throw new APIError('FORBIDDEN', { message: 'm', code: SOME_CODE }); }
+      function b(code: string) { throw new APIError('FORBIDDEN', { message: 'm', code }); }
+      function c() { throw new APIError('FORBIDDEN', { 'code': 'X', message: 'm' }); }
+      function d() { throw new api.APIError('FORBIDDEN', { message: 'm', code: SOME_CODE }); }
+      async function e() {
+        const held = judgeHeldSession({ authGate: await gateOf() });
+        if (!held) return;
+        const { body } = held;
+        throw new APIError('FORBIDDEN', body);
+      }`;
+    expect(verdicts(fixture)).toEqual([true, true, true, true, true]);
+  });
+
+  it('the textual control sees past comments, and counts a member-callee site', () => {
+    const fixture = `
+      // new APIError('FORBIDDEN', { message: 'in a comment' })
+      /** new APIError('X') in a doc block */
+      function a() { throw new api.APIError('FORBIDDEN', { message: 'm', code: C }); }`;
+    expect(textualCount('fixture.ts', fixture)).toBe(1);
+    expect(apiErrorSites('fixture.ts', fixture)).toHaveLength(1);
+  });
+});
@@ -25,6 +25,13 @@
  *     `sys_environment` (the open-source composition) declares the guard
  *     inapplicable without reading anything. The real ObjectQL registry
  *     answers that question in the last section.
+ *
+ * [#24243] Both answers are pinned on their ADR-0112 codes, the refusal's
+ * registered `ORGANIZATION_SLUG_LOCKED_BY_ACTIVE_ENVIRONMENTS` and the read
+ * fault's standard `SERVICE_UNAVAILABLE`, at this level rather than on the
+ * wire: `sys_environment` is a cloud-provided object that no composition in this
+ * repository registers, so on a stock dogfood boot the guard does not apply and
+ * neither answer has a door.
  */
 
 import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
@@ -108,15 +115,19 @@ async function slugGuard(dataEngine: unknown) {
   return (slug: string) => guard({ organization: { slug }, member: { organizationId: ORG.id } });
 }
 
-/** The guard's refusal, asserted on its envelope: better-auth's `FORBIDDEN` / 403, naming the active environments. */
+/**
+ * The guard's refusal, asserted on its envelope: better-auth's `FORBIDDEN` / 403
+ * with its registered ADR-0112 code (#24243), naming the active environments.
+ */
 async function expectSlugRefusal(attempt: Promise<unknown>) {
   const err = (await attempt.then(
     () => undefined,
     (e: unknown) => e,
-  )) as { status?: unknown; statusCode?: unknown; body?: { message?: unknown } } | undefined;
+  )) as { status?: unknown; statusCode?: unknown; body?: { code?: unknown; message?: unknown } } | undefined;
   expect(err, 'the slug change was not refused').toBeTruthy();
   expect(err?.statusCode).toBe(403);
   expect(err?.status).toBe('FORBIDDEN');
+  expect(err?.body?.code).toBe('ORGANIZATION_SLUG_LOCKED_BY_ACTIVE_ENVIRONMENTS');
   expect(String(err?.body?.message)).toMatch(/active.*environment/i);
 }
 
@@ -180,18 +191,20 @@ describe('organization slug guard — on an engine that refuses a principal-less
 
 /**
  * A read that could not answer, asserted on its envelope: better-auth's
- * `SERVICE_UNAVAILABLE` / 503, naming the object whose read failed — and
- * explicitly NOT the guard's `FORBIDDEN` / 403, which is a verdict about the
- * slug change that the guard never reached.
+ * `SERVICE_UNAVAILABLE` / 503 with the standard code of the same name (#24243),
+ * naming the object whose read failed — and explicitly NOT the guard's
+ * `FORBIDDEN` / 403, which is a verdict about the slug change that the guard
+ * never reached.
  */
 async function expectReadFaultRefusal(attempt: Promise<unknown>, object: string) {
   const err = (await attempt.then(
     () => undefined,
     (e: unknown) => e,
-  )) as { status?: unknown; statusCode?: unknown; body?: { message?: unknown }; cause?: unknown } | undefined;
+  )) as { status?: unknown; statusCode?: unknown; body?: { code?: unknown; message?: unknown }; cause?: unknown } | undefined;
   expect(err, 'the slug change was let through on a read that could not answer').toBeTruthy();
   expect(err?.statusCode).toBe(503);
   expect(err?.status).toBe('SERVICE_UNAVAILABLE');
+  expect(err?.body?.code).toBe('SERVICE_UNAVAILABLE');
   expect(String(err?.body?.message)).toContain(`\`${object}\``);
   return err;
 }