@@ -0,0 +1,13 @@
+---
+'@objectstack/spec': minor
+---
+
+spec!: `WebhookSchema` declares `secret` (a credential value) and `headers` (a credential map, as a whole) with `.meta({ credential: 'value' | 'map' })`, and `getMetadataTypeRedactor(type)` gains a third resolution — after explicit registrations and built-ins — a redactor derived from the credential markers on the type's registered schema. Every meta read door now withholds a webhook's `secret` and `headers`, with or without `@objectstack/plugin-webhooks` mounted (ruling B+ on #24966).
+
+**BREAKING:** the `/meta` read doors no longer serve a webhook's `secret` or `headers`.
+
+Clause-②: no (narrowing) — the `/meta` read doors return less for `webhook`: a stored `secret` or non-empty `headers` map is dropped from the served item and named in `redactedKeys`; the cleared forms (an empty string, an empty map) are served as written. A save that omits the two fields keeps the stored values (the metadata protocol's carry-forward); to remove a credential, save its cleared form. The dispatcher reads the declaration itself, so delivery signing is unchanged.
+
+A metadata type that stores a credential in a declared field marks it on its schema instead of registering a redactor; a spec ratchet reds on a credential-named field that carries no marker.
+
+<!-- adr-0087: not-required (no-migration-prescription) no authorable key, export or stored shape is removed or renamed; the read doors serve less, and a stored webhook needs no migration -->
@@ -0,0 +1,220 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+//
+// [ruling B+ on #24966, #24994] Every meta read door withholds a webhook's
+// declared credentials — `secret` (a credential value) and `headers` (a
+// credential map, as a whole) — in BOTH compositions: without
+// `@objectstack/plugin-webhooks`, and with it mounted.
+//
+// The rule under test: `WebhookSchema` marks the two fields with
+// `.meta({ credential: … })`, and `getMetadataTypeRedactor('webhook')`
+// resolves a redactor DERIVED from those markers (`@objectstack/spec/kernel`),
+// present from module load whatever the composition mounts. A webhook's items
+// reach the meta read doors identically with and without the plugin (declared
+// ones through manifest decomposition, saved ones through the meta save door),
+// so a plugin registration would protect only one of the two compositions;
+// this file boots both.
+//
+// Doors pinned, per composition: the meta list (both spellings), the item read,
+// the layered view, the published read, the metadata protocol's list and item
+// reads, and the stored-row data door with its history twin. Each door read
+// carries a positive control (the response names the webhook), so a refusal or
+// an empty answer cannot pass for a withheld credential.
+//
+// Also pinned: the stored record is never mutated (redaction is a serving
+// act); a save of the served form keeps the stored values (the metadata
+// protocol's carry-forward); and, with the plugin mounted, the dispatcher's
+// declared-webhook source still carries both credentials, so delivery signing
+// is unaffected.
+//
+// Disclosure: every credential below is an obviously-fake placeholder, and
+// every assertion is absence by rule, never a served value.
+
+import { describe, it, expect, beforeAll, afterAll } from 'vitest';
+import { bootStack, type VerifyStack } from '@objectstack/verify';
+import { MessagingServicePlugin } from '@objectstack/service-messaging';
+import { WebhookOutboxPlugin } from '@objectstack/plugin-webhooks';
+import { defineStack } from '@objectstack/spec';
+import { ObjectSchema, Field } from '@objectstack/spec/data';
+import { defineWebhook } from '@objectstack/spec/automation';
+
+const SYSTEM = { isSystem: true, positions: [], permissions: [] };
+
+/** Obviously-fake placeholders: absence of these strings is the whole assertion. */
+const DECLARED_SECRET = 'TEST_SECRET_DECLARED_24994';
+const DECLARED_HEADER = 'TEST_HEADER_DECLARED_24994';
+const SAVED_SECRET = 'TEST_SECRET_SAVED_24994';
+const SAVED_HEADER = 'TEST_HEADER_SAVED_24994';
+const PLACEHOLDERS = [DECLARED_SECRET, DECLARED_HEADER, SAVED_SECRET, SAVED_HEADER] as const;
+
+const DECLARED = 'wcr_declared';
+const SAVED = 'wcr_saved';
+
+const WcrTask = ObjectSchema.create({
+  name: 'wcr_task',
+  sharingModel: 'public_read_write',
+  label: 'WCR Task',
+  pluralLabel: 'WCR Tasks',
+  fields: { name: Field.text({ label: 'Name', required: true }) },
+});
+
+const fixture = defineStack({
+  manifest: {
+    id: 'com.dogfood.webhook-credential-redaction',
+    namespace: 'wcr',
+    version: '0.0.0',
+    type: 'app',
+    name: 'Webhook Credential Redaction Fixture',
+    description: 'One object and one declared webhook carrying both declared credential fields, for the meta read-door pins of ruling B+ on #24966.',
+  },
+  objects: [WcrTask],
+  webhooks: [
+    defineWebhook({
+      name: DECLARED,
+      label: 'WCR Declared',
+      object: 'wcr_task',
+      triggers: ['create'],
+      url: 'https://hooks.example/wcr-declared',
+      headers: { 'X-Placeholder': DECLARED_HEADER },
+      secret: DECLARED_SECRET,
+      isActive: false,
+    }),
+  ],
+});
+
+const savedBody = () => ({
+  name: SAVED,
+  label: 'WCR Saved',
+  object: 'wcr_task',
+  triggers: ['update'],
+  url: 'https://hooks.example/wcr-saved',
+  headers: { 'X-Placeholder': SAVED_HEADER },
+  secret: SAVED_SECRET,
+  isActive: false,
+});
+
+const rowsOf = (r: any): any[] => (Array.isArray(r) ? r : Array.isArray(r?.records) ? r.records : Array.isArray(r?.value) ? r.value : []);
+const holdsAPlaceholder = (v: unknown): boolean => {
+  const text = typeof v === 'string' ? v : JSON.stringify(v ?? null);
+  return PLACEHOLDERS.some((p) => text.includes(p));
+};
+const bodyOf = (row: any): Record<string, unknown> =>
+  typeof row?.metadata === 'string' ? JSON.parse(row.metadata) : (row?.metadata ?? {});
+
+const COMPOSITIONS = [
+  { label: 'without plugin-webhooks', plugins: () => [] as unknown[] },
+  { label: 'with plugin-webhooks mounted', plugins: () => [new MessagingServicePlugin(), new WebhookOutboxPlugin()] },
+] as const;
+
+for (const composition of COMPOSITIONS) {
+  describe(`[ruling B+] every meta read door withholds a webhook's declared credentials — ${composition.label}`, () => {
+    let stack: VerifyStack;
+    let admin: string;
+    let member: string;
+    let ql: any;
+    let protocol: any;
+
+    const stored = async (object: 'sys_metadata' | 'sys_metadata_history', name: string) =>
+      rowsOf(await ql.find(object, { where: { type: 'webhook', name }, context: SYSTEM }));
+
+    /** One door read: 200, names the webhook (positive control), and holds no credential. */
+    const expectWithheld = async (token: string, path: string, names: readonly string[]) => {
+      const res = await stack.apiAs(token, 'GET', path);
+      const text = await res.text();
+      expect(res.status, `${path}: ${text.slice(0, 200)}`).toBe(200);
+      for (const name of names) expect(text.includes(name), `${path} names ${name}`).toBe(true);
+      expect(holdsAPlaceholder(text), `${path} withholds the declared credential fields`).toBe(false);
+    };
+
+    beforeAll(async () => {
+      stack = await bootStack(fixture as never, { extraPlugins: composition.plugins() as never });
+      ql = await stack.kernel.getServiceAsync('objectql');
+      protocol = await stack.kernel.getServiceAsync('protocol');
+      admin = await stack.signIn();
+      member = await stack.signUp(`wcr-member-${composition.plugins().length}@redaction.test`);
+      const put = await stack.apiAs(admin, 'PUT', `/meta/webhook/${SAVED}`, savedBody());
+      expect(put.status, await put.clone().text()).toBe(200);
+    }, 180_000);
+
+    afterAll(async () => {
+      await stack?.stop?.();
+    });
+
+    it('guard the guard: the saved webhook is stored with both credential fields, and the plugin is mounted exactly when this composition says so', async () => {
+      const [row] = await stored('sys_metadata', SAVED);
+      expect(bodyOf(row).secret).toBe(SAVED_SECRET);
+      expect(bodyOf(row).headers).toEqual({ 'X-Placeholder': SAVED_HEADER });
+      let declaredService: unknown;
+      try {
+        declaredService = stack.kernel.getService('declaredWebhooks');
+      } catch {
+        declaredService = undefined;
+      }
+      expect(Boolean(declaredService)).toBe(composition.plugins().length > 0);
+    });
+
+    it('the meta list, both spellings, withholds both fields of the declared and the saved webhook', async () => {
+      for (const token of [admin, member]) {
+        await expectWithheld(token, '/meta/webhook', [DECLARED, SAVED]);
+        await expectWithheld(token, '/meta/webhooks', [DECLARED, SAVED]);
+      }
+    });
+
+    it('the item read and the layered view withhold both fields', async () => {
+      for (const token of [admin, member]) {
+        for (const name of [DECLARED, SAVED]) {
+          await expectWithheld(token, `/meta/webhook/${name}`, [name]);
+          await expectWithheld(token, `/meta/webhook/${name}/layers`, [name]);
+        }
+      }
+    });
+
+    it('the published read withholds both fields', async () => {
+      for (const token of [admin, member]) await expectWithheld(token, `/meta/webhook/${SAVED}/published`, [SAVED]);
+    });
+
+    it('the metadata protocol\'s list and item reads withhold both fields', async () => {
+      const listed = await protocol.getMetaItems({ type: 'webhook' });
+      expect(JSON.stringify(listed).includes(SAVED)).toBe(true);
+      expect(holdsAPlaceholder(listed)).toBe(false);
+      for (const name of [DECLARED, SAVED]) {
+        const item = await protocol.getMetaItem({ type: 'webhook', name });
+        expect(JSON.stringify(item).includes(name), name).toBe(true);
+        expect(holdsAPlaceholder(item), name).toBe(false);
+      }
+    });
+
+    it('the stored-row data door and its history twin withhold both fields', async () => {
+      const filter = encodeURIComponent(JSON.stringify({ type: 'webhook', name: SAVED }));
+      await expectWithheld(admin, `/data/sys_metadata?filter=${filter}`, [SAVED]);
+      await expectWithheld(admin, `/data/sys_metadata_history?filter=${filter}`, [SAVED]);
+    });
+
+    it('a save of the served form keeps the stored values (the carry-forward), and the store is never redacted', async () => {
+      const read = await stack.apiAs(admin, 'GET', `/meta/webhook/${SAVED}`);
+      expect(read.status).toBe(200);
+      const json = (await read.json()) as any;
+      const served = (json?.item ?? json?.data?.item ?? json?.data ?? json) as Record<string, unknown>;
+      expect(served?.name).toBe(SAVED);
+      const body = Object.fromEntries(Object.entries(served).filter(([k]) => !k.startsWith('_')));
+      expect(Object.keys(body)).not.toContain('secret');
+      expect(Object.keys(body)).not.toContain('headers');
+
+      const put = await stack.apiAs(admin, 'PUT', `/meta/webhook/${SAVED}`, { ...body, label: 'WCR Saved (edited)' });
+      expect(put.status, await put.clone().text()).toBe(200);
+
+      const [row] = await stored('sys_metadata', SAVED);
+      expect(bodyOf(row).label).toBe('WCR Saved (edited)');
+      expect(bodyOf(row).secret).toBe(SAVED_SECRET);
+      expect(bodyOf(row).headers).toEqual({ 'X-Placeholder': SAVED_HEADER });
+    });
+
+    if (composition.plugins().length > 0) {
+      it('the dispatcher\'s declared-webhook source still carries both credentials: delivery signing is unaffected', async () => {
+        const declaredWebhooks = (await stack.kernel.getServiceAsync('declaredWebhooks')) as any;
+        const declared = await declaredWebhooks.declaredWebhookNamed(DECLARED);
+        expect(declared?.webhook?.secret).toBe(DECLARED_SECRET);
+        expect(declared?.webhook?.headers).toEqual({ 'X-Placeholder': DECLARED_HEADER });
+      });
+    }
+  });
+}
@@ -193,14 +193,26 @@ export const WebhookSchema = lazySchema(() => strictObject({
   url: z.string().url().describe('External webhook endpoint URL'),
   method: z.enum(['GET', 'POST', 'PUT', 'PATCH', 'DELETE']).default('POST').describe('HTTP method'),
 
-  /** Headers */
-  headers: z.record(z.string(), z.string()).optional().describe('Custom HTTP headers'),
+  /**
+   * Headers. A credential MAP as a whole (`.meta({ credential: 'map' })`):
+   * the platform cannot tell which entry of an authored header map carries a
+   * credential, so every meta read door withholds the whole map, and the
+   * schema-derived redactor in `kernel/metadata-type-redaction.ts` is what
+   * reads this marker (ruling B+ on #24966).
+   */
+  headers: z.record(z.string(), z.string()).optional().describe('Custom HTTP headers').meta({ credential: 'map' }),
 
   /** Timeout */
   timeoutMs: z.number().int().min(1000).max(300000).default(30000).describe('Request timeout in milliseconds'),
 
-  /** Security */
-  secret: z.string().optional().describe('Signing secret for HMAC signature verification'),
+  /**
+   * Security. A credential VALUE (`.meta({ credential: 'value' })`): every
+   * meta read door withholds it, derived from this marker by
+   * `kernel/metadata-type-redaction.ts` (ruling B+ on #24966). The dispatcher
+   * reads the declaration itself, never a served copy, so delivery signing is
+   * unaffected.
+   */
+  secret: z.string().optional().describe('Signing secret for HMAC signature verification').meta({ credential: 'value' }),
 
   /** Status */
   isActive: z.boolean().default(true).describe('Whether webhook is active'),