From 2f13a2c3b922b5976ba9cf7baa36fe57d41b0c56 Mon Sep 17 00:00:00 2001
From: abrook <abrook@google.com>
Date: Wed, 1 Oct 2025 09:25:15 -0400
Subject: [PATCH 1/6] Introduce TelemetryOptions allowing telemetry endpoint to
 be specified.

---
 common/api-review/telemetry-react.api.md      | 16 ++++++-
 common/api-review/telemetry.api.md            |  9 +++-
 docs-devsite/_toc.yaml                        |  8 +++-
 docs-devsite/telemetry_.md                    | 39 ++++++++++-----
 docs-devsite/telemetry_.telemetry.md          |  2 +-
 docs-devsite/telemetry_.telemetryoptions.md   | 35 ++++++++++++++
 docs-devsite/telemetry_react.md               | 18 +++++--
 docs-devsite/telemetry_react.telemetry.md     | 48 +++++++++++++++++++
 .../telemetry_react.telemetryoptions.md       | 35 ++++++++++++++
 packages/telemetry/package.json               |  1 +
 packages/telemetry/rollup.config.js           |  4 ++
 packages/telemetry/src/api.ts                 | 21 +++++++-
 .../telemetry/src/logging/logger-provider.ts  |  9 ++--
 packages/telemetry/src/next.test.ts           |  2 +-
 packages/telemetry/src/next.ts                | 37 +++++++-------
 packages/telemetry/src/public-types.ts        | 13 +++++
 packages/telemetry/src/react/index.ts         | 25 +++++-----
 packages/telemetry/src/register.node.ts       |  8 +++-
 packages/telemetry/src/register.ts            |  8 +++-
 packages/telemetry/tsconfig.react.json        |  1 +
 20 files changed, 279 insertions(+), 60 deletions(-)
 create mode 100644 docs-devsite/telemetry_.telemetryoptions.md
 create mode 100644 docs-devsite/telemetry_react.telemetry.md
 create mode 100644 docs-devsite/telemetry_react.telemetryoptions.md

diff --git a/common/api-review/telemetry-react.api.md b/common/api-review/telemetry-react.api.md
index d7eeb9b53ea..53e344cc1ab 100644
--- a/common/api-review/telemetry-react.api.md
+++ b/common/api-review/telemetry-react.api.md
@@ -4,13 +4,27 @@
 
 ```ts
 
+import { FirebaseApp } from '@firebase/app';
 import { FirebaseOptions } from '@firebase/app';
+import { LoggerProvider } from '@opentelemetry/sdk-logs';
 
 // @public
-export function FirebaseTelemetry({ firebaseOptions }: {
+export function FirebaseTelemetry({ firebaseOptions, telemetryOptions }: {
     firebaseOptions?: FirebaseOptions;
+    telemetryOptions?: TelemetryOptions;
 }): null;
 
+// @public
+export interface Telemetry {
+    app: FirebaseApp;
+    loggerProvider: LoggerProvider;
+}
+
+// @public
+export interface TelemetryOptions {
+    endpointUrl?: string;
+}
+
 
 // (No @packageDocumentation comment for this package)
 
diff --git a/common/api-review/telemetry.api.md b/common/api-review/telemetry.api.md
index 623299b1ee8..6a23ce03b80 100644
--- a/common/api-review/telemetry.api.md
+++ b/common/api-review/telemetry.api.md
@@ -16,12 +16,12 @@ export function captureError(telemetry: Telemetry, error: unknown, attributes?:
 export function flush(telemetry: Telemetry): Promise<void>;
 
 // @public
-export function getTelemetry(app?: FirebaseApp): Telemetry;
+export function getTelemetry(app?: FirebaseApp, options?: TelemetryOptions): Telemetry;
 
 export { Instrumentation }
 
 // @public
-export const nextOnRequestError: Instrumentation.onRequestError;
+export function nextOnRequestError(telemetryOptions?: TelemetryOptions): Instrumentation.onRequestError;
 
 // @public
 export interface Telemetry {
@@ -29,6 +29,11 @@ export interface Telemetry {
     loggerProvider: LoggerProvider;
 }
 
+// @public
+export interface TelemetryOptions {
+    endpointUrl?: string;
+}
+
 
 // (No @packageDocumentation comment for this package)
 
diff --git a/docs-devsite/_toc.yaml b/docs-devsite/_toc.yaml
index c55d94327cf..81078cb2618 100644
--- a/docs-devsite/_toc.yaml
+++ b/docs-devsite/_toc.yaml
@@ -699,6 +699,12 @@ toc:
   section:
   - title: Telemetry
     path: /docs/reference/js/telemetry_.telemetry.md
+  - title: TelemetryOptions
+    path: /docs/reference/js/telemetry_.telemetryoptions.md
 - title: telemetry/react
   path: /docs/reference/js/telemetry_react.md
-  section: []
+  section:
+  - title: Telemetry
+    path: /docs/reference/js/telemetry_react.telemetry.md
+  - title: TelemetryOptions
+    path: /docs/reference/js/telemetry_react.telemetryoptions.md
diff --git a/docs-devsite/telemetry_.md b/docs-devsite/telemetry_.md
index 07e5c629012..ae1f827c9e3 100644
--- a/docs-devsite/telemetry_.md
+++ b/docs-devsite/telemetry_.md
@@ -16,16 +16,19 @@ https://github.com/firebase/firebase-js-sdk
 |  Function | Description |
 |  --- | --- |
 |  <b>function(app, ...)</b> |
-|  [getTelemetry(app)](./telemetry_.md#gettelemetry_cf608e1) | Returns the default [Telemetry](./telemetry_.telemetry.md#telemetry_interface) instance that is associated with the provided [FirebaseApp](./app.firebaseapp.md#firebaseapp_interface)<!-- -->. If no instance exists, initializes a new instance with the default settings. |
+|  [getTelemetry(app, options)](./telemetry_.md#gettelemetry_448bdc6) | Returns the default [Telemetry](./telemetry_.telemetry.md#telemetry_interface) instance that is associated with the provided [FirebaseApp](./app.firebaseapp.md#firebaseapp_interface)<!-- -->. If no instance exists, initializes a new instance with the default settings. |
 |  <b>function(telemetry, ...)</b> |
 |  [captureError(telemetry, error, attributes)](./telemetry_.md#captureerror_862e6b3) | Enqueues an error to be uploaded to the Firebase Telemetry API. |
 |  [flush(telemetry)](./telemetry_.md#flush_8975134) | Flushes all enqueued telemetry data immediately, instead of waiting for default batching. |
+|  <b>function(telemetryOptions, ...)</b> |
+|  [nextOnRequestError(telemetryOptions)](./telemetry_.md#nextonrequesterror_3bd5542) | Automatically report uncaught errors from server routes to Firebase Telemetry. |
 
 ## Interfaces
 
 |  Interface | Description |
 |  --- | --- |
-|  [Telemetry](./telemetry_.telemetry.md#telemetry_interface) | An instance of the Firebase Telemetry SDK.<!-- -->Do not create this instance directly. Instead, use [getTelemetry()](./telemetry_.md#gettelemetry_cf608e1)<!-- -->. |
+|  [Telemetry](./telemetry_.telemetry.md#telemetry_interface) | An instance of the Firebase Telemetry SDK.<!-- -->Do not create this instance directly. Instead, use [getTelemetry()](./telemetry_.md#gettelemetry_448bdc6)<!-- -->. |
+|  [TelemetryOptions](./telemetry_.telemetryoptions.md#telemetryoptions_interface) | Options for initialized the Telemetry service using [getTelemetry()](./telemetry_.md#gettelemetry_448bdc6)<!-- -->. |
 
 ## Namespaces
 
@@ -33,22 +36,16 @@ https://github.com/firebase/firebase-js-sdk
 |  --- | --- |
 |  [Instrumentation](./telemetry_.instrumentation.md#instrumentation_namespace) |  |
 
-## Variables
-
-|  Variable | Description |
-|  --- | --- |
-|  [nextOnRequestError](./telemetry_.md#nextonrequesterror) | Automatically report uncaught errors from server routes to Firebase Telemetry. |
-
 ## function(app, ...)
 
-### getTelemetry(app) {:#gettelemetry_cf608e1}
+### getTelemetry(app, options) {:#gettelemetry_448bdc6}
 
 Returns the default [Telemetry](./telemetry_.telemetry.md#telemetry_interface) instance that is associated with the provided [FirebaseApp](./app.firebaseapp.md#firebaseapp_interface)<!-- -->. If no instance exists, initializes a new instance with the default settings.
 
 <b>Signature:</b>
 
 ```typescript
-export declare function getTelemetry(app?: FirebaseApp): Telemetry;
+export declare function getTelemetry(app?: FirebaseApp, options?: TelemetryOptions): Telemetry;
 ```
 
 #### Parameters
@@ -56,6 +53,7 @@ export declare function getTelemetry(app?: FirebaseApp): Telemetry;
 |  Parameter | Type | Description |
 |  --- | --- | --- |
 |  app | [FirebaseApp](./app.firebaseapp.md#firebaseapp_interface) | The [FirebaseApp](./app.firebaseapp.md#firebaseapp_interface) to use. |
+|  options | [TelemetryOptions](./telemetry_.telemetryoptions.md#telemetryoptions_interface) | [TelemetryOptions](./telemetry_.telemetryoptions.md#telemetryoptions_interface) that configure the Telemetry instance. |
 
 <b>Returns:</b>
 
@@ -117,22 +115,37 @@ Promise&lt;void&gt;
 
 a promise which is resolved when all flushes are complete
 
-## nextOnRequestError
+## function(telemetryOptions, ...)
+
+### nextOnRequestError(telemetryOptions) {:#nextonrequesterror_3bd5542}
 
 Automatically report uncaught errors from server routes to Firebase Telemetry.
 
 <b>Signature:</b>
 
 ```typescript
-nextOnRequestError: Instrumentation.onRequestError
+export declare function nextOnRequestError(telemetryOptions?: TelemetryOptions): Instrumentation.onRequestError;
 ```
 
+#### Parameters
+
+|  Parameter | Type | Description |
+|  --- | --- | --- |
+|  telemetryOptions | [TelemetryOptions](./telemetry_.telemetryoptions.md#telemetryoptions_interface) | [TelemetryOptions](./telemetry_.telemetryoptions.md#telemetryoptions_interface) that configure the Telemetry instance. |
+
+<b>Returns:</b>
+
+[Instrumentation.onRequestError](./telemetry_.instrumentation.md#instrumentationonrequesterror)
+
+A request error handler for use in Next.js' instrumentation file
+
 ### Example
 
 
 ```javascript
 // In instrumentation.ts (https://nextjs.org/docs/app/guides/instrumentation):
-export { nextOnRequestError as onRequestError }  from 'firebase/telemetry'
+import { nextOnRequestError } from 'firebase/telemetry'
+export const onRequestError = nextOnRequestError();
 
 ```
 
diff --git a/docs-devsite/telemetry_.telemetry.md b/docs-devsite/telemetry_.telemetry.md
index 6ac8337e178..9ae0536a474 100644
--- a/docs-devsite/telemetry_.telemetry.md
+++ b/docs-devsite/telemetry_.telemetry.md
@@ -12,7 +12,7 @@ https://github.com/firebase/firebase-js-sdk
 # Telemetry interface
 An instance of the Firebase Telemetry SDK.
 
-Do not create this instance directly. Instead, use [getTelemetry()](./telemetry_.md#gettelemetry_cf608e1)<!-- -->.
+Do not create this instance directly. Instead, use [getTelemetry()](./telemetry_.md#gettelemetry_448bdc6)<!-- -->.
 
 <b>Signature:</b>
 
diff --git a/docs-devsite/telemetry_.telemetryoptions.md b/docs-devsite/telemetry_.telemetryoptions.md
new file mode 100644
index 00000000000..27634878dab
--- /dev/null
+++ b/docs-devsite/telemetry_.telemetryoptions.md
@@ -0,0 +1,35 @@
+Project: /docs/reference/js/_project.yaml
+Book: /docs/reference/_book.yaml
+page_type: reference
+
+{% comment %}
+DO NOT EDIT THIS FILE!
+This is generated by the JS SDK team, and any local changes will be
+overwritten. Changes should be made in the source code at
+https://github.com/firebase/firebase-js-sdk
+{% endcomment %}
+
+# TelemetryOptions interface
+Options for initialized the Telemetry service using [getTelemetry()](./telemetry_.md#gettelemetry_448bdc6)<!-- -->.
+
+<b>Signature:</b>
+
+```typescript
+export interface TelemetryOptions 
+```
+
+## Properties
+
+|  Property | Type | Description |
+|  --- | --- | --- |
+|  [endpointUrl](./telemetry_.telemetryoptions.md#telemetryoptionsendpointurl) | string | The URL for the endpoint to which telemetry data should be sent, in the Open Telemetry format. By default, data will be sent to Firebase. |
+
+## TelemetryOptions.endpointUrl
+
+The URL for the endpoint to which telemetry data should be sent, in the Open Telemetry format. By default, data will be sent to Firebase.
+
+<b>Signature:</b>
+
+```typescript
+endpointUrl?: string;
+```
diff --git a/docs-devsite/telemetry_react.md b/docs-devsite/telemetry_react.md
index 8857f508a6f..40d58284958 100644
--- a/docs-devsite/telemetry_react.md
+++ b/docs-devsite/telemetry_react.md
@@ -15,11 +15,18 @@ https://github.com/firebase/firebase-js-sdk
 
 |  Function | Description |
 |  --- | --- |
-|  [FirebaseTelemetry({ firebaseOptions })](./telemetry_react.md#firebasetelemetry_537af3f) | Registers event listeners for uncaught errors.<!-- -->This should be installed near the root of your application. Caught errors, including those implicitly caught by Error Boundaries, will not be captured by this component. |
+|  [FirebaseTelemetry({ firebaseOptions, telemetryOptions })](./telemetry_react.md#firebasetelemetry_f37eb31) | Registers event listeners for uncaught errors.<!-- -->This should be installed near the root of your application. Caught errors, including those implicitly caught by Error Boundaries, will not be captured by this component. |
 
-## function({ firebaseOptions }, ...)
+## Interfaces
 
-### FirebaseTelemetry({ firebaseOptions }) {:#firebasetelemetry_537af3f}
+|  Interface | Description |
+|  --- | --- |
+|  [Telemetry](./telemetry_react.telemetry.md#telemetry_interface) | An instance of the Firebase Telemetry SDK.<!-- -->Do not create this instance directly. Instead, use [getTelemetry()](./telemetry_.md#gettelemetry_448bdc6)<!-- -->. |
+|  [TelemetryOptions](./telemetry_react.telemetryoptions.md#telemetryoptions_interface) | Options for initialized the Telemetry service using [getTelemetry()](./telemetry_.md#gettelemetry_448bdc6)<!-- -->. |
+
+## function({ firebaseOptions, telemetryOptions }, ...)
+
+### FirebaseTelemetry({ firebaseOptions, telemetryOptions }) {:#firebasetelemetry_f37eb31}
 
 Registers event listeners for uncaught errors.
 
@@ -28,8 +35,9 @@ This should be installed near the root of your application. Caught errors, inclu
 <b>Signature:</b>
 
 ```typescript
-export declare function FirebaseTelemetry({ firebaseOptions }: {
+export declare function FirebaseTelemetry({ firebaseOptions, telemetryOptions }: {
     firebaseOptions?: FirebaseOptions;
+    telemetryOptions?: TelemetryOptions;
 }): null;
 ```
 
@@ -37,7 +45,7 @@ export declare function FirebaseTelemetry({ firebaseOptions }: {
 
 |  Parameter | Type | Description |
 |  --- | --- | --- |
-|  { firebaseOptions } | { firebaseOptions?: [FirebaseOptions](./app.firebaseoptions.md#firebaseoptions_interface)<!-- -->; } |  |
+|  { firebaseOptions, telemetryOptions } | { firebaseOptions?: [FirebaseOptions](./app.firebaseoptions.md#firebaseoptions_interface)<!-- -->; telemetryOptions?: [TelemetryOptions](./telemetry_.telemetryoptions.md#telemetryoptions_interface)<!-- -->; } |  |
 
 <b>Returns:</b>
 
diff --git a/docs-devsite/telemetry_react.telemetry.md b/docs-devsite/telemetry_react.telemetry.md
new file mode 100644
index 00000000000..5a767aa609f
--- /dev/null
+++ b/docs-devsite/telemetry_react.telemetry.md
@@ -0,0 +1,48 @@
+Project: /docs/reference/js/_project.yaml
+Book: /docs/reference/_book.yaml
+page_type: reference
+
+{% comment %}
+DO NOT EDIT THIS FILE!
+This is generated by the JS SDK team, and any local changes will be
+overwritten. Changes should be made in the source code at
+https://github.com/firebase/firebase-js-sdk
+{% endcomment %}
+
+# Telemetry interface
+An instance of the Firebase Telemetry SDK.
+
+Do not create this instance directly. Instead, use [getTelemetry()](./telemetry_.md#gettelemetry_448bdc6)<!-- -->.
+
+<b>Signature:</b>
+
+```typescript
+export interface Telemetry 
+```
+
+## Properties
+
+|  Property | Type | Description |
+|  --- | --- | --- |
+|  [app](./telemetry_react.telemetry.md#telemetryapp) | [FirebaseApp](./app.firebaseapp.md#firebaseapp_interface) | The [FirebaseApp](./app.firebaseapp.md#firebaseapp_interface) this [Telemetry](./telemetry_.telemetry.md#telemetry_interface) instance is associated with. |
+|  [loggerProvider](./telemetry_react.telemetry.md#telemetryloggerprovider) | LoggerProvider | The  this [Telemetry](./telemetry_.telemetry.md#telemetry_interface) instance uses. |
+
+## Telemetry.app
+
+The [FirebaseApp](./app.firebaseapp.md#firebaseapp_interface) this [Telemetry](./telemetry_.telemetry.md#telemetry_interface) instance is associated with.
+
+<b>Signature:</b>
+
+```typescript
+app: FirebaseApp;
+```
+
+## Telemetry.loggerProvider
+
+The  this [Telemetry](./telemetry_.telemetry.md#telemetry_interface) instance uses.
+
+<b>Signature:</b>
+
+```typescript
+loggerProvider: LoggerProvider;
+```
diff --git a/docs-devsite/telemetry_react.telemetryoptions.md b/docs-devsite/telemetry_react.telemetryoptions.md
new file mode 100644
index 00000000000..fa3263d9160
--- /dev/null
+++ b/docs-devsite/telemetry_react.telemetryoptions.md
@@ -0,0 +1,35 @@
+Project: /docs/reference/js/_project.yaml
+Book: /docs/reference/_book.yaml
+page_type: reference
+
+{% comment %}
+DO NOT EDIT THIS FILE!
+This is generated by the JS SDK team, and any local changes will be
+overwritten. Changes should be made in the source code at
+https://github.com/firebase/firebase-js-sdk
+{% endcomment %}
+
+# TelemetryOptions interface
+Options for initialized the Telemetry service using [getTelemetry()](./telemetry_.md#gettelemetry_448bdc6)<!-- -->.
+
+<b>Signature:</b>
+
+```typescript
+export interface TelemetryOptions 
+```
+
+## Properties
+
+|  Property | Type | Description |
+|  --- | --- | --- |
+|  [endpointUrl](./telemetry_react.telemetryoptions.md#telemetryoptionsendpointurl) | string | The URL for the endpoint to which telemetry data should be sent, in the Open Telemetry format. By default, data will be sent to Firebase. |
+
+## TelemetryOptions.endpointUrl
+
+The URL for the endpoint to which telemetry data should be sent, in the Open Telemetry format. By default, data will be sent to Firebase.
+
+<b>Signature:</b>
+
+```typescript
+endpointUrl?: string;
+```
diff --git a/packages/telemetry/package.json b/packages/telemetry/package.json
index d1c6a9c8ab2..84c2cf25b7d 100644
--- a/packages/telemetry/package.json
+++ b/packages/telemetry/package.json
@@ -70,6 +70,7 @@
   },
   "dependencies": {
     "@firebase/component": "0.7.0",
+    "@firebase/util": "1.13.0",
     "@opentelemetry/api": "1.9.0",
     "@opentelemetry/api-logs": "0.203.0",
     "@opentelemetry/exporter-logs-otlp-http": "0.203.0",
diff --git a/packages/telemetry/rollup.config.js b/packages/telemetry/rollup.config.js
index fbeb28a5bd8..a9a6df94188 100644
--- a/packages/telemetry/rollup.config.js
+++ b/packages/telemetry/rollup.config.js
@@ -94,6 +94,10 @@ const reactBuilds = [
           {
             src: 'dist/src/react/index.d.ts',
             dest: 'dist/react'
+          },
+          {
+            src: 'dist/src/public-types.d.ts',
+            dest: 'dist'
           }
         ]
       })
diff --git a/packages/telemetry/src/api.ts b/packages/telemetry/src/api.ts
index 27b785ff2a4..b7aa7683395 100644
--- a/packages/telemetry/src/api.ts
+++ b/packages/telemetry/src/api.ts
@@ -16,8 +16,9 @@
  */
 
 import { _getProvider, FirebaseApp, getApp } from '@firebase/app';
+import { deepEqual } from '@firebase/util';
 import { TELEMETRY_TYPE } from './constants';
-import { Telemetry } from './public-types';
+import { Telemetry, TelemetryOptions } from './public-types';
 import { Provider } from '@firebase/component';
 import { AnyValueMap, SeverityNumber } from '@opentelemetry/api-logs';
 import { trace } from '@opentelemetry/api';
@@ -40,17 +41,33 @@ declare module '@firebase/component' {
  * ```
  *
  * @param app - The {@link @firebase/app#FirebaseApp} to use.
+ * @param options - {@link TelemetryOptions} that configure the Telemetry instance.
  * @returns The default {@link Telemetry} instance for the given {@link @firebase/app#FirebaseApp}.
  *
  * @public
  */
-export function getTelemetry(app: FirebaseApp = getApp()): Telemetry {
+export function getTelemetry(
+  app: FirebaseApp = getApp(),
+  options?: TelemetryOptions
+): Telemetry {
   // Dependencies
   const telemetryProvider: Provider<'telemetry'> = _getProvider(
     app,
     TELEMETRY_TYPE
   );
 
+  if (telemetryProvider.isInitialized()) {
+    const initialOptions = telemetryProvider.getOptions();
+    if (
+      (!initialOptions && !options) ||
+      (initialOptions && options && deepEqual(initialOptions, options))
+    ) {
+      return telemetryProvider.getImmediate();
+    }
+    throw new Error('Firebase Telemetry is already initialized');
+  }
+
+  telemetryProvider.initialize({ options });
   return telemetryProvider.getImmediate();
 }
 
diff --git a/packages/telemetry/src/logging/logger-provider.ts b/packages/telemetry/src/logging/logger-provider.ts
index bd982f04cfe..cc22e22a297 100644
--- a/packages/telemetry/src/logging/logger-provider.ts
+++ b/packages/telemetry/src/logging/logger-provider.ts
@@ -37,13 +37,16 @@ import { FetchTransportEdge } from './fetch-transport.edge';
  *
  * @internal
  */
-export function createLoggerProvider(): LoggerProvider {
+export function createLoggerProvider(endpointUrl: string): LoggerProvider {
   const resource = resourceFromAttributes({
     [ATTR_SERVICE_NAME]: 'firebase_telemetry_service'
   });
-  const otlpEndpoint = `${process.env.OTEL_ENDPOINT}/api/v1/logs`;
+  if (endpointUrl.endsWith('/')) {
+    endpointUrl = endpointUrl.slice(0, -1);
+  }
+  const otlpEndpoint = `${endpointUrl}/api/v1/logs`;
 
-  if (process?.env?.NEXT_RUNTIME === 'edge') {
+  if (typeof process !== 'undefined' && process?.env?.NEXT_RUNTIME === 'edge') {
     // We need a slightly custom implementation for the Edge Runtime, because it doesn't have access
     // to many features available in Node.
     const logExporter = new OTLPLogExporterEdge({ url: otlpEndpoint });
diff --git a/packages/telemetry/src/next.test.ts b/packages/telemetry/src/next.test.ts
index 9a6c1fb1e54..259b4b0f87a 100644
--- a/packages/telemetry/src/next.test.ts
+++ b/packages/telemetry/src/next.test.ts
@@ -66,7 +66,7 @@ describe('nextOnRequestError', () => {
       revalidateReason: undefined
     };
 
-    await nextOnRequestError(error, errorRequest, errorContext);
+    await nextOnRequestError()(error, errorRequest, errorContext);
 
     expect(getTelemetryStub).to.have.been.calledOnceWith(fakeApp);
     expect(captureErrorStub).to.have.been.calledOnceWith(fakeTelemetry, error, {
diff --git a/packages/telemetry/src/next.ts b/packages/telemetry/src/next.ts
index a5d06fbf15d..e7d5e2654ec 100644
--- a/packages/telemetry/src/next.ts
+++ b/packages/telemetry/src/next.ts
@@ -19,6 +19,7 @@ import { getApp } from '@firebase/app';
 import { captureError, getTelemetry } from './api';
 // eslint-disable-next-line import/no-extraneous-dependencies
 import { Instrumentation } from 'next';
+import { TelemetryOptions } from './public-types';
 
 export { Instrumentation };
 
@@ -28,25 +29,29 @@ export { Instrumentation };
  * @example
  * ```javascript
  * // In instrumentation.ts (https://nextjs.org/docs/app/guides/instrumentation):
- * export { nextOnRequestError as onRequestError }  from 'firebase/telemetry'
+ * import { nextOnRequestError } from 'firebase/telemetry'
+ * export const onRequestError = nextOnRequestError();
  * ```
  *
+ * @param telemetryOptions - {@link TelemetryOptions} that configure the Telemetry instance.
+ * @returns A request error handler for use in Next.js' instrumentation file
+ *
  * @public
  */
-export const nextOnRequestError: Instrumentation.onRequestError = async (
-  error,
-  errorRequest,
-  errorContext
-) => {
-  const telemetry = getTelemetry(getApp());
+export function nextOnRequestError(
+  telemetryOptions?: TelemetryOptions
+): Instrumentation.onRequestError {
+  return async (error, errorRequest, errorContext) => {
+    const telemetry = getTelemetry(getApp(), telemetryOptions);
 
-  const attributes = {
-    'nextjs_path': errorRequest.path,
-    'nextjs_method': errorRequest.method,
-    'nextjs_router_kind': errorContext.routerKind,
-    'nextjs_route_path': errorContext.routePath,
-    'nextjs_route_type': errorContext.routeType
-  };
+    const attributes = {
+      'nextjs_path': errorRequest.path,
+      'nextjs_method': errorRequest.method,
+      'nextjs_router_kind': errorContext.routerKind,
+      'nextjs_route_path': errorContext.routePath,
+      'nextjs_route_type': errorContext.routeType
+    };
 
-  captureError(telemetry, error, attributes);
-};
+    captureError(telemetry, error, attributes);
+  };
+}
diff --git a/packages/telemetry/src/public-types.ts b/packages/telemetry/src/public-types.ts
index 3ebe4196d98..852c72221fd 100644
--- a/packages/telemetry/src/public-types.ts
+++ b/packages/telemetry/src/public-types.ts
@@ -34,3 +34,16 @@ export interface Telemetry {
   /** The {@link LoggerProvider} this {@link Telemetry} instance uses. */
   loggerProvider: LoggerProvider;
 }
+
+/**
+ * Options for initialized the Telemetry service using {@link getTelemetry | getTelemetry()}.
+ *
+ * @public
+ */
+export interface TelemetryOptions {
+  /**
+   * The URL for the endpoint to which telemetry data should be sent, in the Open Telemetry format.
+   * By default, data will be sent to Firebase.
+   */
+  endpointUrl?: string;
+}
diff --git a/packages/telemetry/src/react/index.ts b/packages/telemetry/src/react/index.ts
index f1fde0d7525..c43d898d41c 100644
--- a/packages/telemetry/src/react/index.ts
+++ b/packages/telemetry/src/react/index.ts
@@ -15,20 +15,15 @@
  * limitations under the License.
  */
 
-import { FirebaseOptions, initializeApp } from '@firebase/app';
+import { FirebaseOptions, getApp, initializeApp } from '@firebase/app';
 import { registerTelemetry } from '../register';
 import { captureError, getTelemetry } from '../api';
+import { TelemetryOptions } from '../public-types';
 import { useEffect } from 'react';
 
 registerTelemetry();
 
-function errorListener(event: ErrorEvent): void {
-  captureError(getTelemetry(), event.error, {});
-}
-
-function unhandledRejectionListener(event: PromiseRejectionEvent): void {
-  captureError(getTelemetry(), event.reason, {});
-}
+export * from '../public-types';
 
 /**
  * Registers event listeners for uncaught errors.
@@ -45,22 +40,30 @@ function unhandledRejectionListener(event: PromiseRejectionEvent): void {
  * ```
  *
  * @param firebaseOptions - Options to run {@link @firebase/app#initializeApp}. If this is not provided, initializeApp needs to be called explicitly elsewhere in your application.
+ * @param telemetryOptions - {@link TelemetryOptions} that configure the Telemetry instance.
  * @returns The default {@link Telemetry} instance for the given {@link @firebase/app#FirebaseApp}.
  *
  * @public
  */
 export function FirebaseTelemetry({
-  firebaseOptions
+  firebaseOptions,
+  telemetryOptions
 }: {
   firebaseOptions?: FirebaseOptions;
+  telemetryOptions?: TelemetryOptions;
 }): null {
   useEffect(() => {
     if (typeof window === 'undefined') {
       return;
     }
 
-    // TODO: This will be removed once there is a default endpoint
-    process.env.OTEL_ENDPOINT = window.location.origin;
+    const errorListener = (event: ErrorEvent): void => {
+      captureError(getTelemetry(getApp(), telemetryOptions), event.error, {});
+    };
+
+    const unhandledRejectionListener = (event: PromiseRejectionEvent): void => {
+      captureError(getTelemetry(getApp(), telemetryOptions), event.reason, {});
+    };
 
     try {
       if (firebaseOptions) {
diff --git a/packages/telemetry/src/register.node.ts b/packages/telemetry/src/register.node.ts
index c5b17dc3388..890bac89d5c 100644
--- a/packages/telemetry/src/register.node.ts
+++ b/packages/telemetry/src/register.node.ts
@@ -21,15 +21,19 @@ import { TELEMETRY_TYPE } from './constants';
 import { name, version } from '../package.json';
 import { TelemetryService } from './service';
 import { createLoggerProvider } from './logging/logger-provider';
+import { TelemetryOptions } from './public-types';
 
 export function registerTelemetry(): void {
   _registerComponent(
     new Component(
       TELEMETRY_TYPE,
-      container => {
+      (container, { options }: { options?: TelemetryOptions }) => {
+        // TODO: change to default endpoint once it exists
+        const endpointUrl = options?.endpointUrl || 'http://localhost';
+
         // getImmediate for FirebaseApp will always succeed
         const app = container.getProvider('app').getImmediate();
-        const loggerProvider = createLoggerProvider();
+        const loggerProvider = createLoggerProvider(endpointUrl);
         const appCheckProvider = container.getProvider('app-check-internal');
 
         return new TelemetryService(app, loggerProvider, appCheckProvider);
diff --git a/packages/telemetry/src/register.ts b/packages/telemetry/src/register.ts
index 2a75bf96157..cbcb5416f38 100644
--- a/packages/telemetry/src/register.ts
+++ b/packages/telemetry/src/register.ts
@@ -21,15 +21,19 @@ import { TELEMETRY_TYPE } from './constants';
 import { name, version } from '../package.json';
 import { TelemetryService } from './service';
 import { createLoggerProvider } from './logging/logger-provider';
+import { TelemetryOptions } from './public-types';
 
 export function registerTelemetry(): void {
   _registerComponent(
     new Component(
       TELEMETRY_TYPE,
-      (container, {}) => {
+      (container, { options }: { options?: TelemetryOptions }) => {
+        // TODO: change to default endpoint once it exists
+        const endpointUrl = options?.endpointUrl || 'http://localhost';
+
         // getImmediate for FirebaseApp will always succeed
         const app = container.getProvider('app').getImmediate();
-        const loggerProvider = createLoggerProvider();
+        const loggerProvider = createLoggerProvider(endpointUrl);
         const appCheckProvider = container.getProvider('app-check-internal');
 
         return new TelemetryService(app, loggerProvider, appCheckProvider);
diff --git a/packages/telemetry/tsconfig.react.json b/packages/telemetry/tsconfig.react.json
index de2b1885562..324d71ec811 100644
--- a/packages/telemetry/tsconfig.react.json
+++ b/packages/telemetry/tsconfig.react.json
@@ -5,5 +5,6 @@
     "declarationDir": "dist/react",
     "jsx": "react"
   },
+  // "include": ["src/react/index.ts", "src/public-types.ts"]
   "include": ["src/react/index.ts"]
 }
\ No newline at end of file

From 5dcab36b6490b81576e657f2fe818fecf71ff0b3 Mon Sep 17 00:00:00 2001
From: abrook <abrook@google.com>
Date: Thu, 2 Oct 2025 11:34:01 -0400
Subject: [PATCH 2/6] Fix typo

---
 packages/telemetry/tsconfig.react.json | 1 -
 1 file changed, 1 deletion(-)

diff --git a/packages/telemetry/tsconfig.react.json b/packages/telemetry/tsconfig.react.json
index 324d71ec811..de2b1885562 100644
--- a/packages/telemetry/tsconfig.react.json
+++ b/packages/telemetry/tsconfig.react.json
@@ -5,6 +5,5 @@
     "declarationDir": "dist/react",
     "jsx": "react"
   },
-  // "include": ["src/react/index.ts", "src/public-types.ts"]
   "include": ["src/react/index.ts"]
 }
\ No newline at end of file

From 060a623784cfc70c0db21554dd3b87f7158e7bd0 Mon Sep 17 00:00:00 2001
From: abrook <abrook@google.com>
Date: Thu, 2 Oct 2025 11:44:25 -0400
Subject: [PATCH 3/6] update lock

---
 yarn.lock | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/yarn.lock b/yarn.lock
index e6e4692d51e..ebe977434b3 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1325,6 +1325,17 @@
   resolved "https://registry.npmjs.org/@eslint/js/-/js-8.57.1.tgz#de633db3ec2ef6a3c89e2f19038063e8a122e2c2"
   integrity sha512-d9zaMRSTIKDLhctzH12MtXvJKSSUhaHcjV+2Z+GK+EEY7XKpP5yR4x+N3TAcHTcu963nIr+TMcCb4DBCYX1z6Q==
 
+"@firebase/app@0.14.2":
+  version "0.14.2"
+  resolved "https://registry.npmjs.org/@firebase/app/-/app-0.14.2.tgz#b97ca1a28d6a7bd0490af4c75005c1ba27228280"
+  integrity sha512-Ecx2ig/JLC9ayIQwZHqm41Tzlf4c1WUuFhFUZB1y+JIJqDRE579x7Uil7tKT8MwDpOPwrK5ZtpxdSsrfy/LF8Q==
+  dependencies:
+    "@firebase/component" "0.7.0"
+    "@firebase/logger" "0.5.0"
+    "@firebase/util" "1.13.0"
+    idb "7.1.1"
+    tslib "^2.1.0"
+
 "@gar/promisify@^1.0.1":
   version "1.1.3"
   resolved "https://registry.npmjs.org/@gar/promisify/-/promisify-1.1.3.tgz#555193ab2e3bb3b6adc3d551c9c030d9e860daf6"

From 0e81ec4a47982e57363ea7abdc2ebc3e051e8ee6 Mon Sep 17 00:00:00 2001
From: abrook <abrook@google.com>
Date: Thu, 2 Oct 2025 11:53:12 -0400
Subject: [PATCH 4/6] update version of firebase/app

---
 packages/telemetry/package.json |  2 +-
 yarn.lock                       | 11 -----------
 2 files changed, 1 insertion(+), 12 deletions(-)

diff --git a/packages/telemetry/package.json b/packages/telemetry/package.json
index 84c2cf25b7d..60b250f143b 100644
--- a/packages/telemetry/package.json
+++ b/packages/telemetry/package.json
@@ -83,7 +83,7 @@
   },
   "license": "Apache-2.0",
   "devDependencies": {
-    "@firebase/app": "0.14.2",
+    "@firebase/app": "0.14.3",
     "@opentelemetry/sdk-trace-web": "2.1.0",
     "@rollup/plugin-json": "6.1.0",
     "@testing-library/dom": "10.4.1",
diff --git a/yarn.lock b/yarn.lock
index ebe977434b3..e6e4692d51e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1325,17 +1325,6 @@
   resolved "https://registry.npmjs.org/@eslint/js/-/js-8.57.1.tgz#de633db3ec2ef6a3c89e2f19038063e8a122e2c2"
   integrity sha512-d9zaMRSTIKDLhctzH12MtXvJKSSUhaHcjV+2Z+GK+EEY7XKpP5yR4x+N3TAcHTcu963nIr+TMcCb4DBCYX1z6Q==
 
-"@firebase/app@0.14.2":
-  version "0.14.2"
-  resolved "https://registry.npmjs.org/@firebase/app/-/app-0.14.2.tgz#b97ca1a28d6a7bd0490af4c75005c1ba27228280"
-  integrity sha512-Ecx2ig/JLC9ayIQwZHqm41Tzlf4c1WUuFhFUZB1y+JIJqDRE579x7Uil7tKT8MwDpOPwrK5ZtpxdSsrfy/LF8Q==
-  dependencies:
-    "@firebase/component" "0.7.0"
-    "@firebase/logger" "0.5.0"
-    "@firebase/util" "1.13.0"
-    idb "7.1.1"
-    tslib "^2.1.0"
-
 "@gar/promisify@^1.0.1":
   version "1.1.3"
   resolved "https://registry.npmjs.org/@gar/promisify/-/promisify-1.1.3.tgz#555193ab2e3bb3b6adc3d551c9c030d9e860daf6"

From 9d6ac47ddb548b233fab8cc8e7b608a03db38f5d Mon Sep 17 00:00:00 2001
From: abrook <abrook@google.com>
Date: Mon, 6 Oct 2025 10:26:24 -0400
Subject: [PATCH 5/6] Normalize getTelemetry initialization

---
 packages/telemetry/package.json         |  1 -
 packages/telemetry/src/api.test.ts      | 68 ++++++++++++++++++++++++-
 packages/telemetry/src/api.ts           | 20 ++------
 packages/telemetry/src/helpers.test.ts  | 37 ++++++++++++++
 packages/telemetry/src/helpers.ts       | 42 +++++++++++++++
 packages/telemetry/src/register.node.ts | 13 +++--
 packages/telemetry/src/register.ts      | 13 +++--
 7 files changed, 168 insertions(+), 26 deletions(-)
 create mode 100644 packages/telemetry/src/helpers.test.ts
 create mode 100644 packages/telemetry/src/helpers.ts

diff --git a/packages/telemetry/package.json b/packages/telemetry/package.json
index 60b250f143b..d3626cee099 100644
--- a/packages/telemetry/package.json
+++ b/packages/telemetry/package.json
@@ -70,7 +70,6 @@
   },
   "dependencies": {
     "@firebase/component": "0.7.0",
-    "@firebase/util": "1.13.0",
     "@opentelemetry/api": "1.9.0",
     "@opentelemetry/api-logs": "0.203.0",
     "@opentelemetry/exporter-logs-otlp-http": "0.203.0",
diff --git a/packages/telemetry/src/api.test.ts b/packages/telemetry/src/api.test.ts
index ad13bc967ce..2085aa879f1 100644
--- a/packages/telemetry/src/api.test.ts
+++ b/packages/telemetry/src/api.test.ts
@@ -25,7 +25,17 @@ import {
   SimpleSpanProcessor,
   WebTracerProvider
 } from '@opentelemetry/sdk-trace-web';
-import { captureError, flush } from './api';
+import {
+  FirebaseApp,
+  initializeApp,
+  _registerComponent,
+  _addOrOverwriteComponent
+} from '@firebase/app';
+import { Component, ComponentType } from '@firebase/component';
+import { FirebaseAppCheckInternal } from '@firebase/app-check-interop-types';
+import { captureError, flush, getTelemetry } from './api';
+import { TelemetryService } from './service';
+import { registerTelemetry } from './register';
 
 const PROJECT_ID = 'my-project';
 const APP_ID = 'my-appid';
@@ -65,6 +75,33 @@ describe('Top level API', () => {
     emittedLogs.length = 0;
   });
 
+  describe('getTelemetry()', () => {
+    it('works without options', () => {
+      expect(getTelemetry(getFakeApp())).to.be.instanceOf(TelemetryService);
+      // Two instances are the same
+      expect(getTelemetry(getFakeApp())).to.equal(getTelemetry(getFakeApp()));
+    });
+
+    it('works with options: no endpointUrl', () => {
+      expect(getTelemetry(getFakeApp(), {})).to.equal(
+        getTelemetry(getFakeApp())
+      );
+    });
+
+    it('works with options: endpointUrl set', () => {
+      const app = getFakeApp();
+      expect(getTelemetry(app, { endpointUrl: 'http://endpoint1' })).to.equal(
+        getTelemetry(app, { endpointUrl: 'http://endpoint1' })
+      );
+      expect(
+        getTelemetry(app, { endpointUrl: 'http://endpoint1' })
+      ).not.to.equal(getTelemetry(app, { endpointUrl: 'http://endpoint2' }));
+      expect(
+        getTelemetry(app, { endpointUrl: 'http://endpoint1' })
+      ).not.to.equal(getTelemetry(app, {}));
+    });
+  });
+
   describe('captureError()', () => {
     it('should capture an Error object correctly', () => {
       const error = new Error('This is a test error');
@@ -189,3 +226,32 @@ describe('Top level API', () => {
     });
   });
 });
+
+function getFakeApp(): FirebaseApp {
+  registerTelemetry();
+  _registerComponent(
+    new Component(
+      'app-check-internal',
+      () => {
+        return {} as FirebaseAppCheckInternal;
+      },
+      ComponentType.PUBLIC
+    )
+  );
+  const app = initializeApp({});
+  _addOrOverwriteComponent(
+    app,
+    //@ts-ignore
+    new Component(
+      'heartbeat',
+      // @ts-ignore
+      () => {
+        return {
+          triggerHeartbeat: () => {}
+        };
+      },
+      ComponentType.PUBLIC
+    )
+  );
+  return app;
+}
diff --git a/packages/telemetry/src/api.ts b/packages/telemetry/src/api.ts
index b7aa7683395..c6b091cefaa 100644
--- a/packages/telemetry/src/api.ts
+++ b/packages/telemetry/src/api.ts
@@ -16,13 +16,13 @@
  */
 
 import { _getProvider, FirebaseApp, getApp } from '@firebase/app';
-import { deepEqual } from '@firebase/util';
 import { TELEMETRY_TYPE } from './constants';
 import { Telemetry, TelemetryOptions } from './public-types';
 import { Provider } from '@firebase/component';
 import { AnyValueMap, SeverityNumber } from '@opentelemetry/api-logs';
 import { trace } from '@opentelemetry/api';
 import { TelemetryService } from './service';
+import { encodeInstanceIdentifier } from './helpers';
 
 declare module '@firebase/component' {
   interface NameServiceMapping {
@@ -50,25 +50,13 @@ export function getTelemetry(
   app: FirebaseApp = getApp(),
   options?: TelemetryOptions
 ): Telemetry {
-  // Dependencies
   const telemetryProvider: Provider<'telemetry'> = _getProvider(
     app,
     TELEMETRY_TYPE
   );
-
-  if (telemetryProvider.isInitialized()) {
-    const initialOptions = telemetryProvider.getOptions();
-    if (
-      (!initialOptions && !options) ||
-      (initialOptions && options && deepEqual(initialOptions, options))
-    ) {
-      return telemetryProvider.getImmediate();
-    }
-    throw new Error('Firebase Telemetry is already initialized');
-  }
-
-  telemetryProvider.initialize({ options });
-  return telemetryProvider.getImmediate();
+  const finalOptions: TelemetryOptions = options || {};
+  const identifier = encodeInstanceIdentifier(finalOptions);
+  return telemetryProvider.getImmediate({ identifier });
 }
 
 /**
diff --git a/packages/telemetry/src/helpers.test.ts b/packages/telemetry/src/helpers.test.ts
new file mode 100644
index 00000000000..f44888fb1bd
--- /dev/null
+++ b/packages/telemetry/src/helpers.test.ts
@@ -0,0 +1,37 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { expect } from 'chai';
+import { encodeInstanceIdentifier, decodeInstanceIdentifier } from './helpers';
+import { TelemetryOptions } from './public-types';
+
+describe('Identifier encoding/decoding', () => {
+  it('encodes/decodes empty options', () => {
+    const encoded = encodeInstanceIdentifier({});
+    const decoded = decodeInstanceIdentifier(encoded);
+    expect(decoded).to.deep.equal({});
+  });
+
+  it('encodes/decodes full options', () => {
+    const options: TelemetryOptions = {
+      endpointUrl: 'http://myendpoint'
+    };
+    const encoded = encodeInstanceIdentifier(options);
+    const decoded = decodeInstanceIdentifier(encoded);
+    expect(decoded).to.deep.equal(options);
+  });
+});
diff --git a/packages/telemetry/src/helpers.ts b/packages/telemetry/src/helpers.ts
new file mode 100644
index 00000000000..c1f2ec9aab8
--- /dev/null
+++ b/packages/telemetry/src/helpers.ts
@@ -0,0 +1,42 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { TelemetryOptions } from './public-types';
+
+/**
+ * Encodes {@link TelemetryOptions} into a string that will be used to uniquely identify
+ * {@link Telemetry} instances by endpoint URL.
+ *
+ * @internal
+ */
+export function encodeInstanceIdentifier(options: TelemetryOptions): string {
+  return options.endpointUrl || '';
+}
+
+/**
+ * Decodes an instance identifier string into {@link TelemetryOptions}.
+ *
+ * @internal
+ */
+export function decodeInstanceIdentifier(identifier: string): TelemetryOptions {
+  if (identifier) {
+    return {
+      endpointUrl: identifier
+    };
+  }
+  return {};
+}
diff --git a/packages/telemetry/src/register.node.ts b/packages/telemetry/src/register.node.ts
index 890bac89d5c..994d3411da1 100644
--- a/packages/telemetry/src/register.node.ts
+++ b/packages/telemetry/src/register.node.ts
@@ -21,15 +21,20 @@ import { TELEMETRY_TYPE } from './constants';
 import { name, version } from '../package.json';
 import { TelemetryService } from './service';
 import { createLoggerProvider } from './logging/logger-provider';
-import { TelemetryOptions } from './public-types';
+import { decodeInstanceIdentifier } from './helpers';
 
 export function registerTelemetry(): void {
   _registerComponent(
     new Component(
       TELEMETRY_TYPE,
-      (container, { options }: { options?: TelemetryOptions }) => {
+      (container, { instanceIdentifier }) => {
+        if (instanceIdentifier === undefined) {
+          throw new Error('TelemetryService instance identifier is undefined');
+        }
+
+        const options = decodeInstanceIdentifier(instanceIdentifier);
         // TODO: change to default endpoint once it exists
-        const endpointUrl = options?.endpointUrl || 'http://localhost';
+        const endpointUrl = options.endpointUrl || 'http://localhost';
 
         // getImmediate for FirebaseApp will always succeed
         const app = container.getProvider('app').getImmediate();
@@ -39,7 +44,7 @@ export function registerTelemetry(): void {
         return new TelemetryService(app, loggerProvider, appCheckProvider);
       },
       ComponentType.PUBLIC
-    )
+    ).setMultipleInstances(true)
   );
 
   registerVersion(name, version, 'node');
diff --git a/packages/telemetry/src/register.ts b/packages/telemetry/src/register.ts
index cbcb5416f38..027f0d575b2 100644
--- a/packages/telemetry/src/register.ts
+++ b/packages/telemetry/src/register.ts
@@ -21,15 +21,20 @@ import { TELEMETRY_TYPE } from './constants';
 import { name, version } from '../package.json';
 import { TelemetryService } from './service';
 import { createLoggerProvider } from './logging/logger-provider';
-import { TelemetryOptions } from './public-types';
+import { decodeInstanceIdentifier } from './helpers';
 
 export function registerTelemetry(): void {
   _registerComponent(
     new Component(
       TELEMETRY_TYPE,
-      (container, { options }: { options?: TelemetryOptions }) => {
+      (container, { instanceIdentifier }) => {
+        if (instanceIdentifier === undefined) {
+          throw new Error('TelemetryService instance identifier is undefined');
+        }
+
+        const options = decodeInstanceIdentifier(instanceIdentifier);
         // TODO: change to default endpoint once it exists
-        const endpointUrl = options?.endpointUrl || 'http://localhost';
+        const endpointUrl = options.endpointUrl || 'http://localhost';
 
         // getImmediate for FirebaseApp will always succeed
         const app = container.getProvider('app').getImmediate();
@@ -39,7 +44,7 @@ export function registerTelemetry(): void {
         return new TelemetryService(app, loggerProvider, appCheckProvider);
       },
       ComponentType.PUBLIC
-    )
+    ).setMultipleInstances(true)
   );
 
   registerVersion(name, version);

From 304b275aeea4b20b6da82d7a55613fef6425cd6d Mon Sep 17 00:00:00 2001
From: abrook <abrook@google.com>
Date: Mon, 6 Oct 2025 14:11:25 -0400
Subject: [PATCH 6/6] Clean up service init

---
 packages/telemetry/src/api.ts           |  4 +--
 packages/telemetry/src/helpers.test.ts  | 37 ----------------------
 packages/telemetry/src/helpers.ts       | 42 -------------------------
 packages/telemetry/src/register.node.ts |  4 +--
 packages/telemetry/src/register.ts      |  4 +--
 5 files changed, 3 insertions(+), 88 deletions(-)
 delete mode 100644 packages/telemetry/src/helpers.test.ts
 delete mode 100644 packages/telemetry/src/helpers.ts

diff --git a/packages/telemetry/src/api.ts b/packages/telemetry/src/api.ts
index c6b091cefaa..0b93fe555fe 100644
--- a/packages/telemetry/src/api.ts
+++ b/packages/telemetry/src/api.ts
@@ -22,7 +22,6 @@ import { Provider } from '@firebase/component';
 import { AnyValueMap, SeverityNumber } from '@opentelemetry/api-logs';
 import { trace } from '@opentelemetry/api';
 import { TelemetryService } from './service';
-import { encodeInstanceIdentifier } from './helpers';
 
 declare module '@firebase/component' {
   interface NameServiceMapping {
@@ -54,8 +53,7 @@ export function getTelemetry(
     app,
     TELEMETRY_TYPE
   );
-  const finalOptions: TelemetryOptions = options || {};
-  const identifier = encodeInstanceIdentifier(finalOptions);
+  const identifier = options?.endpointUrl || '';
   return telemetryProvider.getImmediate({ identifier });
 }
 
diff --git a/packages/telemetry/src/helpers.test.ts b/packages/telemetry/src/helpers.test.ts
deleted file mode 100644
index f44888fb1bd..00000000000
--- a/packages/telemetry/src/helpers.test.ts
+++ /dev/null
@@ -1,37 +0,0 @@
-/**
- * @license
- * Copyright 2025 Google LLC
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-import { expect } from 'chai';
-import { encodeInstanceIdentifier, decodeInstanceIdentifier } from './helpers';
-import { TelemetryOptions } from './public-types';
-
-describe('Identifier encoding/decoding', () => {
-  it('encodes/decodes empty options', () => {
-    const encoded = encodeInstanceIdentifier({});
-    const decoded = decodeInstanceIdentifier(encoded);
-    expect(decoded).to.deep.equal({});
-  });
-
-  it('encodes/decodes full options', () => {
-    const options: TelemetryOptions = {
-      endpointUrl: 'http://myendpoint'
-    };
-    const encoded = encodeInstanceIdentifier(options);
-    const decoded = decodeInstanceIdentifier(encoded);
-    expect(decoded).to.deep.equal(options);
-  });
-});
diff --git a/packages/telemetry/src/helpers.ts b/packages/telemetry/src/helpers.ts
deleted file mode 100644
index c1f2ec9aab8..00000000000
--- a/packages/telemetry/src/helpers.ts
+++ /dev/null
@@ -1,42 +0,0 @@
-/**
- * @license
- * Copyright 2025 Google LLC
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-import { TelemetryOptions } from './public-types';
-
-/**
- * Encodes {@link TelemetryOptions} into a string that will be used to uniquely identify
- * {@link Telemetry} instances by endpoint URL.
- *
- * @internal
- */
-export function encodeInstanceIdentifier(options: TelemetryOptions): string {
-  return options.endpointUrl || '';
-}
-
-/**
- * Decodes an instance identifier string into {@link TelemetryOptions}.
- *
- * @internal
- */
-export function decodeInstanceIdentifier(identifier: string): TelemetryOptions {
-  if (identifier) {
-    return {
-      endpointUrl: identifier
-    };
-  }
-  return {};
-}
diff --git a/packages/telemetry/src/register.node.ts b/packages/telemetry/src/register.node.ts
index 994d3411da1..58988dd6f13 100644
--- a/packages/telemetry/src/register.node.ts
+++ b/packages/telemetry/src/register.node.ts
@@ -21,7 +21,6 @@ import { TELEMETRY_TYPE } from './constants';
 import { name, version } from '../package.json';
 import { TelemetryService } from './service';
 import { createLoggerProvider } from './logging/logger-provider';
-import { decodeInstanceIdentifier } from './helpers';
 
 export function registerTelemetry(): void {
   _registerComponent(
@@ -32,9 +31,8 @@ export function registerTelemetry(): void {
           throw new Error('TelemetryService instance identifier is undefined');
         }
 
-        const options = decodeInstanceIdentifier(instanceIdentifier);
         // TODO: change to default endpoint once it exists
-        const endpointUrl = options.endpointUrl || 'http://localhost';
+        const endpointUrl = instanceIdentifier || 'http://localhost';
 
         // getImmediate for FirebaseApp will always succeed
         const app = container.getProvider('app').getImmediate();
diff --git a/packages/telemetry/src/register.ts b/packages/telemetry/src/register.ts
index 027f0d575b2..8d7fb8d5397 100644
--- a/packages/telemetry/src/register.ts
+++ b/packages/telemetry/src/register.ts
@@ -21,7 +21,6 @@ import { TELEMETRY_TYPE } from './constants';
 import { name, version } from '../package.json';
 import { TelemetryService } from './service';
 import { createLoggerProvider } from './logging/logger-provider';
-import { decodeInstanceIdentifier } from './helpers';
 
 export function registerTelemetry(): void {
   _registerComponent(
@@ -32,9 +31,8 @@ export function registerTelemetry(): void {
           throw new Error('TelemetryService instance identifier is undefined');
         }
 
-        const options = decodeInstanceIdentifier(instanceIdentifier);
         // TODO: change to default endpoint once it exists
-        const endpointUrl = options.endpointUrl || 'http://localhost';
+        const endpointUrl = instanceIdentifier || 'http://localhost';
 
         // getImmediate for FirebaseApp will always succeed
         const app = container.getProvider('app').getImmediate();