diff --git a/libs/tools/generator/core/src/types/forwarder-options.ts b/libs/tools/generator/core/src/types/forwarder-options.ts
index e258c55a516..06084261283 100644
--- a/libs/tools/generator/core/src/types/forwarder-options.ts
+++ b/libs/tools/generator/core/src/types/forwarder-options.ts
@@ -7,26 +7,65 @@ import {
 
 import { EmailDomainSettings, EmailPrefixSettings } from "../engine";
 
+// FIXME: this type alias is in place for legacy support purposes;
+//   when replacing the forwarder implementation, eliminate `ForwarderId` and
+//   `IntegrationId`. The proper type is `VendorId`.
 /** Identifiers for email forwarding services.
  *  @remarks These are used to select forwarder-specific options.
  *  The must be kept in sync with the forwarder implementations.
  */
 export type ForwarderId = IntegrationId;
 
-/** Options common to all forwarder APIs */
+/** Options common to all forwarder APIs
+ *  @deprecated use {@link ForwarderOptions} instead.
+ */
 export type ApiOptions = ApiSettings & IntegrationRequest;
 
-/** Api configuration for forwarders that support self-hosted installations. */
+/** Api configuration for forwarders that support self-hosted installations.
+ *  @deprecated use {@link ForwarderOptions} instead.
+ */
 export type SelfHostedApiOptions = SelfHostedApiSettings & IntegrationRequest;
 
-/** Api configuration for forwarders that support custom domains. */
+/** Api configuration for forwarders that support custom domains.
+ *  @deprecated use {@link ForwarderOptions} instead.
+ */
 export type EmailDomainOptions = EmailDomainSettings;
 
-/** Api configuration for forwarders that support custom email parts. */
+/** Api configuration for forwarders that support custom email parts.
+ *  @deprecated use {@link ForwarderOptions} instead.
+ */
 export type EmailPrefixOptions = EmailDomainSettings & EmailPrefixSettings;
 
-// These options are used by all forwarders; each forwarder uses a different set,
-// as defined by `GeneratorMetadata<T>.capabilities.fields`.
+/** These options are used by all forwarders; each forwarder uses a different set,
+ *   as defined by `GeneratorMetadata<T>.capabilities.fields`.
+ */
 export type ForwarderOptions = Partial<
-  EmailDomainSettings & EmailPrefixSettings & SelfHostedApiSettings
+  {
+    /** bearer token that authenticates bitwarden to the forwarder.
+     *  This is required to issue an API request.
+     */
+    token: string;
+
+    /** The base URL of the forwarder's API.
+     *  When this is undefined or empty, the forwarder's default production API is used.
+     */
+    baseUrl: string;
+
+    /** The domain part of the generated email address.
+     *  @remarks The domain should be authorized by the forwarder before
+     *           submitting a request through bitwarden.
+     *  @example If the domain is `domain.io` and the generated username
+     *  is `jd`, then the generated email address will be `jd@domain.io`
+     */
+    domain: string;
+
+    /** A prefix joined to the generated email address' username.
+     *  @example If the prefix is `foo`, the generated username is `bar`,
+     *  and the domain is `domain.io`, then the generated email address is
+     *  `foobar@domain.io`.
+     */
+    prefix: string;
+  } & EmailDomainSettings &
+    EmailPrefixSettings &
+    SelfHostedApiSettings
 >;