From a021eafaf235dd08c0835d91ee714aca24c4605e Mon Sep 17 00:00:00 2001
From: Svend <svendbjarne@gmail.com>
Date: Sat, 22 Aug 2026 10:19:03 +0200
Subject: [PATCH] fix(client): a client with more plugins fits a narrower
 client type again (#10907)

Co-authored-by: Taesu <bytaesu@gmail.com>
---
 .changeset/hydrate-session-variance.md          |  5 +++++
 packages/better-auth/src/client/client.test.ts  | 14 ++++++++++++++
 packages/better-auth/src/client/lynx/index.ts   |  4 +---
 packages/better-auth/src/client/react/index.ts  |  4 +---
 packages/better-auth/src/client/solid/index.ts  |  4 +---
 packages/better-auth/src/client/svelte/index.ts |  4 +---
 packages/better-auth/src/client/vanilla.ts      |  4 +---
 packages/better-auth/src/client/vue/index.ts    |  4 +---
 8 files changed, 25 insertions(+), 18 deletions(-)
 create mode 100644 .changeset/hydrate-session-variance.md

diff --git a/.changeset/hydrate-session-variance.md b/.changeset/hydrate-session-variance.md
new file mode 100644
index 0000000000..69f9b2d4e9
--- /dev/null
+++ b/.changeset/hydrate-session-variance.md
@@ -0,0 +1,5 @@
+---
+"better-auth": patch
+---
+
+A client created with more plugins is again assignable to a client type declaring fewer plugins, as in 1.6.
diff --git a/packages/better-auth/src/client/client.test.ts b/packages/better-auth/src/client/client.test.ts
index 7cb8f6b2aa..8fe9124bb5 100644
--- a/packages/better-auth/src/client/client.test.ts
+++ b/packages/better-auth/src/client/client.test.ts
@@ -17,6 +17,7 @@ import {
 	organizationClient,
 	twoFactorClient,
 } from "./plugins";
+import type { ReactAuthClient } from "./react";
 import { createAuthClient as createReactClient } from "./react";
 import { createAuthClient as createSolidClient } from "./solid";
 import { createAuthClient as createSvelteClient } from "./svelte";
@@ -419,6 +420,19 @@ describe("run time proxy", async () => {
 });
 
 describe("type", () => {
+	/**
+	 * @see https://github.com/better-auth/better-auth/issues/10897
+	 */
+	it("keeps a client with more plugins assignable to a client type with fewer plugins", () => {
+		type EmailOtpClient = ReactAuthClient<{
+			plugins: [ReturnType<typeof emailOTPClient>];
+		}>;
+		const client = createReactClient({
+			plugins: [emailOTPClient(), adminClient()],
+		});
+		expectTypeOf(client).toMatchTypeOf<EmailOtpClient>();
+	});
+
 	it("should not infer non-action endpoints", () => {
 		const client = createReactClient({
 			plugins: [testClientPlugin()],
diff --git a/packages/better-auth/src/client/lynx/index.ts b/packages/better-auth/src/client/lynx/index.ts
index afa9decdc1..22390a8298 100644
--- a/packages/better-auth/src/client/lynx/index.ts
+++ b/packages/better-auth/src/client/lynx/index.ts
@@ -60,9 +60,7 @@ export type LynxAuthClient<Option extends BetterAuthClientOptions> =
 	UnionToIntersection<InferResolvedHooks<Option>> &
 		InferClientAPI<Option> &
 		InferActions<Option> & {
-			hydrateSession: (
-				session: NonNullable<ClientSession<Option>> | null,
-			) => void;
+			hydrateSession(session: NonNullable<ClientSession<Option>> | null): void;
 			useSession: () => {
 				data: ClientSession<Option>;
 				isPending: boolean;
diff --git a/packages/better-auth/src/client/react/index.ts b/packages/better-auth/src/client/react/index.ts
index c7f2fafefd..4f5457a7b6 100644
--- a/packages/better-auth/src/client/react/index.ts
+++ b/packages/better-auth/src/client/react/index.ts
@@ -60,9 +60,7 @@ export type ReactAuthClient<Option extends BetterAuthClientOptions> =
 	UnionToIntersection<InferResolvedHooks<Option>> &
 		InferClientAPI<Option> &
 		InferActions<Option> & {
-			hydrateSession: (
-				session: NonNullable<ClientSession<Option>> | null,
-			) => void;
+			hydrateSession(session: NonNullable<ClientSession<Option>> | null): void;
 			useSession: () => {
 				data: ClientSession<Option>;
 				isPending: boolean;
diff --git a/packages/better-auth/src/client/solid/index.ts b/packages/better-auth/src/client/solid/index.ts
index eaa82764aa..76063243fc 100644
--- a/packages/better-auth/src/client/solid/index.ts
+++ b/packages/better-auth/src/client/solid/index.ts
@@ -61,9 +61,7 @@ export type SolidAuthClient<Option extends BetterAuthClientOptions> =
 	UnionToIntersection<InferResolvedHooks<Option>> &
 		InferClientAPI<Option> &
 		InferActions<Option> & {
-			hydrateSession: (
-				session: NonNullable<ClientSession<Option>> | null,
-			) => void;
+			hydrateSession(session: NonNullable<ClientSession<Option>> | null): void;
 			useSession: () => Accessor<{
 				data: ClientSession<Option>;
 				isPending: boolean;
diff --git a/packages/better-auth/src/client/svelte/index.ts b/packages/better-auth/src/client/svelte/index.ts
index 5a50e6b38a..5ac7ff7665 100644
--- a/packages/better-auth/src/client/svelte/index.ts
+++ b/packages/better-auth/src/client/svelte/index.ts
@@ -56,9 +56,7 @@ export type SvelteAuthClient<Option extends BetterAuthClientOptions> =
 	UnionToIntersection<InferResolvedHooks<Option>> &
 		InferClientAPI<Option> &
 		InferActions<Option> & {
-			hydrateSession: (
-				session: NonNullable<ClientSession<Option>> | null,
-			) => void;
+			hydrateSession(session: NonNullable<ClientSession<Option>> | null): void;
 			useSession: () => Atom<{
 				data: ClientSession<Option>;
 				error: BetterFetchError | null;
diff --git a/packages/better-auth/src/client/vanilla.ts b/packages/better-auth/src/client/vanilla.ts
index 1a2751296e..6cb8525070 100644
--- a/packages/better-auth/src/client/vanilla.ts
+++ b/packages/better-auth/src/client/vanilla.ts
@@ -56,9 +56,7 @@ export type AuthClient<Option extends BetterAuthClientOptions> =
 	UnionToIntersection<InferResolvedHooks<Option>> &
 		InferClientAPI<Option> &
 		InferActions<Option> & {
-			hydrateSession: (
-				session: NonNullable<ClientSession<Option>> | null,
-			) => void;
+			hydrateSession(session: NonNullable<ClientSession<Option>> | null): void;
 			useSession: Atom<{
 				data: ClientSession<Option>;
 				error: BetterFetchError | null;
diff --git a/packages/better-auth/src/client/vue/index.ts b/packages/better-auth/src/client/vue/index.ts
index 44c5f4858d..7ca910ade4 100644
--- a/packages/better-auth/src/client/vue/index.ts
+++ b/packages/better-auth/src/client/vue/index.ts
@@ -88,9 +88,7 @@ export type VueAuthClient<Option extends BetterAuthClientOptions> =
 	UnionToIntersection<InferResolvedHooks<Option>> &
 		InferClientAPI<Option> &
 		InferActions<Option> & {
-			hydrateSession: (
-				session: NonNullable<ClientSession<Option>> | null,
-			) => void;
+			hydrateSession(session: NonNullable<ClientSession<Option>> | null): void;
 			useSession: VueUseSession<Option>;
 			$Infer: {
 				Session: NonNullable<ClientSession<Option>>;