diff --git a/src/features/dns/records.test.ts b/src/features/dns/records.test.ts
new file mode 100644
index 0000000..1ddd8ca
--- /dev/null
+++ b/src/features/dns/records.test.ts
@@ -0,0 +1,22 @@
+/*
+ * SPDX-FileCopyrightText: 2026 Coffey Labs LLC
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { describe, expect, it } from 'vitest';
+import { DEFAULT_KINDS, RECORD_GROUPS } from './records';
+
+describe('DEFAULT_KINDS', () => {
+  it('leaves off the records that can break something else', () => {
+    expect(DEFAULT_KINDS).not.toContain('tlsa');
+    expect(DEFAULT_KINDS).not.toContain('caa');
+    expect(DEFAULT_KINDS).toContain('dkim');
+    expect(DEFAULT_KINDS).toContain('mx');
+  });
+
+  it('warns before CAA is switched on', () => {
+    const caa = RECORD_GROUPS.flatMap((g) => g.kinds).find((k) => k.kind === 'caa');
+    expect(caa?.caution).toMatch(/refused at its next renewal/);
+  });
+});
diff --git a/src/features/dns/records.ts b/src/features/dns/records.ts
index 7937852..658fb26 100644
--- a/src/features/dns/records.ts
+++ b/src/features/dns/records.ts
@@ -63,11 +63,21 @@ export const RECORD_GROUPS: RecordGroup[] = [
     id: 'certs',
     title: 'Limit who can issue certificates',
     why: 'Names the certificate authorities allowed to issue for this domain.',
-    kinds: [{ kind: 'caa', label: 'Certificate authorities (CAA)' }],
+    kinds: [
+      {
+        kind: 'caa',
+        label: 'Certificate authorities (CAA)',
+        caution:
+          "Covers every name under this domain and ties it to this server's ACME account. Another ACME client under this domain, like certbot on a web server, is refused at its next renewal.",
+      },
+    ],
   },
 ];
 
-/** The guided default: everything but TLSA, which needs DNSSEC to mean anything. */
+/**
+ * The guided default: everything but TLSA, which needs DNSSEC to mean anything,
+ * and CAA, which can stop other ACME clients under the domain from renewing.
+ */
 export const DEFAULT_KINDS: RecordKind[] = RECORD_GROUPS.flatMap((g) => g.kinds.map((k) => k.kind)).filter(
-  (k) => k !== 'tlsa',
+  (k) => k !== 'tlsa' && k !== 'caa',
 );