diff --git a/apps/mobile/src/features/cloud/publicConfig.test.ts b/apps/mobile/src/features/cloud/publicConfig.test.ts
index 0307fcdab304aa42bb9c86be6f55245ef7b8320a..05bf1a8fbccdc822a6b74a35368947a4c2a35ea6 100644
--- a/apps/mobile/src/features/cloud/publicConfig.test.ts
+++ b/apps/mobile/src/features/cloud/publicConfig.test.ts
@@ -1,6 +1,11 @@
 import { describe, expect, it, vi } from "vite-plus/test";
 
-import { hasTracingPublicConfig, resolveCloudPublicConfig } from "./publicConfig";
+import {
+  CloudPublicConfigMissingError,
+  hasTracingPublicConfig,
+  resolveCloudPublicConfig,
+  resolveRelayClerkTokenOptions,
+} from "./publicConfig";
 
 vi.mock("expo-constants", () => ({
   default: {
@@ -11,6 +16,12 @@ vi.mock("expo-constants", () => ({
 }));
 
 describe("resolveCloudPublicConfig", () => {
+  it("reports the missing Clerk JWT template as structured configuration", () => {
+    expect(() => resolveRelayClerkTokenOptions()).toThrowError(
+      new CloudPublicConfigMissingError({ key: "T3CODE_CLERK_JWT_TEMPLATE" }),
+    );
+  });
+
   it("returns no cloud configuration for an unconfigured build", () => {
     expect(resolveCloudPublicConfig({})).toEqual({
       clerk: {
diff --git a/apps/mobile/src/features/cloud/publicConfig.ts b/apps/mobile/src/features/cloud/publicConfig.ts
index 2d304da7c0274a8fb267c299ef5c1c3c649577aa..93a78fa4f44edda9bccb43ad8b251db764c7b46d 100644
--- a/apps/mobile/src/features/cloud/publicConfig.ts
+++ b/apps/mobile/src/features/cloud/publicConfig.ts
@@ -1,6 +1,18 @@
 import Constants from "expo-constants";
 import { relayClerkTokenOptions } from "@t3tools/shared/relayAuth";
 import { normalizeSecureRelayUrl } from "@t3tools/shared/relayUrl";
+import * as Schema from "effect/Schema";
+
+export class CloudPublicConfigMissingError extends Schema.TaggedErrorClass<CloudPublicConfigMissingError>()(
+  "CloudPublicConfigMissingError",
+  {
+    key: Schema.Literal("T3CODE_CLERK_JWT_TEMPLATE"),
+  },
+) {
+  override get message(): string {
+    return `${this.key} is not configured.`;
+  }
+}
 
 export interface CloudPublicConfig {
   readonly clerk: {
@@ -87,7 +99,7 @@ export function hasTracingPublicConfig(
 export function resolveRelayClerkTokenOptions() {
   const { jwtTemplate } = resolveCloudPublicConfig().clerk;
   if (!jwtTemplate) {
-    throw new Error("T3CODE_CLERK_JWT_TEMPLATE is not configured.");
+    throw new CloudPublicConfigMissingError({ key: "T3CODE_CLERK_JWT_TEMPLATE" });
   }
   return relayClerkTokenOptions(jwtTemplate);
 }
diff --git a/apps/web/src/cloud/publicConfig.test.ts b/apps/web/src/cloud/publicConfig.test.ts
index bb188d0b110e7e4fc7389b463a888cf374516e57..d42aa34baa26cb2cb88c82171d251130546a08da 100644
--- a/apps/web/src/cloud/publicConfig.test.ts
+++ b/apps/web/src/cloud/publicConfig.test.ts
@@ -1,6 +1,10 @@
 import { afterEach, describe, expect, it, vi } from "vite-plus/test";
 
-import { hasCloudPublicConfig } from "./publicConfig.ts";
+import {
+  CloudPublicConfigMissingError,
+  hasCloudPublicConfig,
+  resolveRelayClerkTokenOptions,
+} from "./publicConfig.ts";
 
 afterEach(() => {
   vi.unstubAllEnvs();
@@ -30,4 +34,12 @@ describe("hasCloudPublicConfig", () => {
 
     expect(hasCloudPublicConfig()).toBe(false);
   });
+
+  it("reports the missing Clerk JWT template as structured configuration", () => {
+    vi.stubEnv("VITE_CLERK_JWT_TEMPLATE", "");
+
+    expect(() => resolveRelayClerkTokenOptions()).toThrowError(
+      new CloudPublicConfigMissingError({ key: "T3CODE_CLERK_JWT_TEMPLATE" }),
+    );
+  });
 });
diff --git a/apps/web/src/cloud/publicConfig.ts b/apps/web/src/cloud/publicConfig.ts
index f7b3ca6bc31ecb456cc76479792a5b22e7c423b6..d9d0e5f44cb65073d8ca68473cba1067577d97ce 100644
--- a/apps/web/src/cloud/publicConfig.ts
+++ b/apps/web/src/cloud/publicConfig.ts
@@ -1,5 +1,17 @@
 import { relayClerkTokenOptions } from "@t3tools/shared/relayAuth";
 import { normalizeSecureRelayUrl } from "@t3tools/shared/relayUrl";
+import * as Schema from "effect/Schema";
+
+export class CloudPublicConfigMissingError extends Schema.TaggedErrorClass<CloudPublicConfigMissingError>()(
+  "CloudPublicConfigMissingError",
+  {
+    key: Schema.Literal("T3CODE_CLERK_JWT_TEMPLATE"),
+  },
+) {
+  override get message(): string {
+    return `${this.key} is not configured.`;
+  }
+}
 
 export interface CloudPublicConfig {
   readonly clerkPublishableKey: string | null;
@@ -65,7 +77,7 @@ export function hasCloudPublicConfig(): boolean {
 export function resolveRelayClerkTokenOptions() {
   const { clerkJwtTemplate } = resolveCloudPublicConfig();
   if (!clerkJwtTemplate) {
-    throw new Error("T3CODE_CLERK_JWT_TEMPLATE is not configured.");
+    throw new CloudPublicConfigMissingError({ key: "T3CODE_CLERK_JWT_TEMPLATE" });
   }
   return relayClerkTokenOptions(clerkJwtTemplate);
 }