diff --git a/.github/workflows/check.yml b/.github/workflows/check.yml
index e53e097694..2f0f9e2cbc 100644
--- a/.github/workflows/check.yml
+++ b/.github/workflows/check.yml
@@ -189,6 +189,8 @@ jobs:
       ALGOLIA_APPLICATION_ID: ${{ secrets.ALGOLIA_APPLICATION_ID }}
       ALGOLIA_ADMIN_KEY: ${{ secrets.ALGOLIA_ADMIN_KEY }}
       MONITORING_API_KEY: ${{ secrets.MONITORING_API_KEY }}
+      METIS_APPLICATION_ID: ${{ secrets.METIS_APPLICATION_ID }}
+      METIS_API_KEY: ${{ secrets.METIS_API_KEY }}
     name: client javascript${{ needs.setup.outputs.RUN_GEN_JAVASCRIPT == 'true' && format('@{0}', fromJSON(needs.setup.outputs.JAVASCRIPT_DATA).version) || '' }}
     steps:
       - uses: actions/checkout@v4
diff --git a/generators/src/main/java/com/algolia/codegen/cts/tests/TestsRequest.java b/generators/src/main/java/com/algolia/codegen/cts/tests/TestsRequest.java
index 384f38451e..62b7869194 100644
--- a/generators/src/main/java/com/algolia/codegen/cts/tests/TestsRequest.java
+++ b/generators/src/main/java/com/algolia/codegen/cts/tests/TestsRequest.java
@@ -81,7 +81,11 @@ public void run(Map<String, CodegenModel> models, Map<String, CodegenOperation>
     List<Object> blocksE2E = new ArrayList<>();
     ParametersWithDataType paramsType = new ParametersWithDataType(models, language, client, false);
 
-    bundle.put("e2eApiKey", client.equals("monitoring") ? "MONITORING_API_KEY" : "ALGOLIA_ADMIN_KEY");
+    bundle.put("e2eAppID", client.equals("composition") ? "METIS_APPLICATION_ID" : "ALGOLIA_APPLICATION_ID");
+    bundle.put(
+      "e2eApiKey",
+      client.equals("composition") ? "METIS_API_KEY" : (client.equals("monitoring") ? "MONITORING_API_KEY" : "ALGOLIA_ADMIN_KEY")
+    );
     bundle.put("useEchoRequester", true);
 
     for (Map.Entry<String, CodegenOperation> entry : operations.entrySet()) {
diff --git a/playground/.env.example b/playground/.env.example
index a7b291d2bb..4d7f6f7c62 100644
--- a/playground/.env.example
+++ b/playground/.env.example
@@ -10,3 +10,6 @@ SEARCH_INDEX=""
 SEARCH_QUERY=""
 
 ANALYTICS_INDEX=""
+
+METIS_APPLICATION_ID=
+METIS_API_KEY=
diff --git a/playground/javascript/node/algoliasearch.ts b/playground/javascript/node/algoliasearch.ts
index a9e21f5e52..247699e5d5 100644
--- a/playground/javascript/node/algoliasearch.ts
+++ b/playground/javascript/node/algoliasearch.ts
@@ -80,7 +80,7 @@ async function testAlgoliasearch() {
   }
 
   try {
-    const analyticsClient = client.initAnalytics({region: 'de'});
+    const analyticsClient = client.initAnalytics({ region: 'de' });
 
     const res = await analyticsClient.getTopFilterForAttribute({
       attribute: 'myAttribute1,myAttribute2',
@@ -97,7 +97,7 @@ async function testAlgoliasearch() {
   }
 
   try {
-    const abtestingClient = client.initAbtesting({region: 'us'});
+    const abtestingClient = client.initAbtesting({ region: 'us' });
 
     const res = await abtestingClient.getABTest({
       id: 42,
diff --git a/playground/javascript/node/composition.ts b/playground/javascript/node/composition.ts
index d9ec0f7c60..9b18a76762 100644
--- a/playground/javascript/node/composition.ts
+++ b/playground/javascript/node/composition.ts
@@ -1,17 +1,44 @@
 import { ApiError } from '@algolia/client-common';
 import { compositionClient } from '@algolia/client-composition';
 
-const appId = process.env.ALGOLIA_APPLICATION_ID || '**** APP_ID *****';
-const apiKey = process.env.ALGOLIA_ADMIN_KEY || '**** ADMIN_KEY *****';
+const appId = process.env.METIS_APPLICATION_ID || '**** APP_ID *****';
+const apiKey = process.env.METIS_API_KEY || '**** ADMIN_KEY *****';
 
 // Init client with appId and apiKey
 const client = compositionClient(appId, apiKey);
 
 async function testComposition() {
   try {
-    const res = await client.listCompositions();
-
+    // create a new composition
+    /*
+    const res = await client.multipleBatch({
+      requests: [
+        {
+          action: 'upsert',
+          body: {
+            objectID: 'id1',
+            description: 'the first ever composition from the client',
+            behavior: {
+              injection: {
+                main: {
+                  source: {
+                    search: {
+                      index: 'cts_e2e_small',
+                    },
+                  },
+                },
+              },
+            },
+          },
+        },
+      ],
+    });
     console.log(`[OK]`, res);
+    */
+
+    const compos = await client.listCompositions();
+
+    console.log(`[OK]`, compos);
   } catch (e) {
     if (e instanceof ApiError) {
       return console.log(`[${e.status}] ${e.message}`, e.stackTrace, e);
diff --git a/playground/javascript/node/search.ts b/playground/javascript/node/search.ts
index 26bc2a304f..054d3f470f 100644
--- a/playground/javascript/node/search.ts
+++ b/playground/javascript/node/search.ts
@@ -1,6 +1,5 @@
 import { ApiError } from '@algolia/client-common';
-import { apiClientVersion, searchClient } from '@algolia/client-search';
-import { SearchQuery } from '@algolia/client-search';
+import { apiClientVersion, searchClient, SearchQuery } from '@algolia/client-search';
 
 const appId = process.env.ALGOLIA_APPLICATION_ID || '**** APP_ID *****';
 const apiKey = process.env.ALGOLIA_ADMIN_KEY || '**** SEARCH_API_KEY *****';
diff --git a/templates/csharp/tests/e2e/e2e.mustache b/templates/csharp/tests/e2e/e2e.mustache
index 037b35631e..ad871b6cee 100644
--- a/templates/csharp/tests/e2e/e2e.mustache
+++ b/templates/csharp/tests/e2e/e2e.mustache
@@ -25,10 +25,10 @@ public class {{client}}RequestTestsE2E
   {
     DotEnv.Load(options: new DotEnvOptions(ignoreExceptions: true, probeForEnv: true, probeLevelsToSearch: 8, envFilePaths: new[] { ".env" }));
 
-    var appId = Environment.GetEnvironmentVariable("ALGOLIA_APPLICATION_ID");
+    var appId = Environment.GetEnvironmentVariable("{{e2eAppID}}");
     if (appId == null)
     {
-      throw new Exception("please provide an `ALGOLIA_APPLICATION_ID` env var for e2e tests");
+      throw new Exception("please provide an `{{e2eAppID}}` env var for e2e tests");
     }
 
     var apiKey = Environment.GetEnvironmentVariable("{{e2eApiKey}}");
diff --git a/templates/go/tests/e2e/e2e.mustache b/templates/go/tests/e2e/e2e.mustache
index 3d413e53a4..2382998148 100644
--- a/templates/go/tests/e2e/e2e.mustache
+++ b/templates/go/tests/e2e/e2e.mustache
@@ -15,11 +15,11 @@ import (
 func createE2E{{#lambda.titlecase}}{{clientPrefix}}{{/lambda.titlecase}}Client(t *testing.T) *{{clientPrefix}}.APIClient {
   t.Helper()
 
-  appID := os.Getenv("ALGOLIA_APPLICATION_ID")
+  appID := os.Getenv("{{e2eAppID}}")
   if appID == "" && os.Getenv("CI") != "true" {
     err := godotenv.Load("../../../../.env")
     require.NoError(t, err)
-    appID = os.Getenv("ALGOLIA_APPLICATION_ID")
+    appID = os.Getenv("{{e2eAppID}}")
   }
   apiKey := os.Getenv("{{e2eApiKey}}")
   client, err := {{clientPrefix}}.NewClient(appID, apiKey, {{#hasRegionalHost}}{{clientPrefix}}.{{#lambda.uppercase}}{{defaultRegion}}{{/lambda.uppercase}},{{/hasRegionalHost}})
diff --git a/templates/java/tests/e2e/e2e.mustache b/templates/java/tests/e2e/e2e.mustache
index e6c2c7ffea..2dc150c0cc 100644
--- a/templates/java/tests/e2e/e2e.mustache
+++ b/templates/java/tests/e2e/e2e.mustache
@@ -24,10 +24,10 @@ class {{client}}RequestsTestsE2E {
         this.json = JsonMapper.builder().configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false).build();
        
         if ("true".equals(System.getenv("CI"))) {
-          this.client = new {{client}}(System.getenv("ALGOLIA_APPLICATION_ID"), System.getenv("{{e2eApiKey}}"){{#hasRegionalHost}}, "{{defaultRegion}}"{{/hasRegionalHost}});
+          this.client = new {{client}}(System.getenv("{{e2eAppID}}"), System.getenv("{{e2eApiKey}}"){{#hasRegionalHost}}, "{{defaultRegion}}"{{/hasRegionalHost}});
         } else {
           Dotenv dotenv = Dotenv.configure().directory("../../").load();
-          this.client = new {{client}}(dotenv.get("ALGOLIA_APPLICATION_ID"), dotenv.get("{{e2eApiKey}}"){{#hasRegionalHost}}, "{{defaultRegion}}"{{/hasRegionalHost}});
+          this.client = new {{client}}(dotenv.get("{{e2eAppID}}"), dotenv.get("{{e2eApiKey}}"){{#hasRegionalHost}}, "{{defaultRegion}}"{{/hasRegionalHost}});
         }
     }
 
diff --git a/templates/javascript/tests/e2e/e2e.mustache b/templates/javascript/tests/e2e/e2e.mustache
index 079424f392..867f8a2fd1 100644
--- a/templates/javascript/tests/e2e/e2e.mustache
+++ b/templates/javascript/tests/e2e/e2e.mustache
@@ -14,15 +14,15 @@ import { compositionClient } from '@algolia/client-composition';
 {{/isCompositionClient}}
 import type { RequestOptions } from '@algolia/client-common';
 
-if (!process.env.ALGOLIA_APPLICATION_ID) {
-  throw new Error("please provide an `ALGOLIA_APPLICATION_ID` env var for e2e tests");
+if (!process.env.{{e2eAppID}}) {
+  throw new Error("please provide an `{{e2eAppID}}` env var for e2e tests");
 }
 
 if (!process.env.{{e2eApiKey}}) {
   throw new Error("please provide an `{{e2eApiKey}}` env var for e2e tests");
 }
 
-const client = {{^isCompositionClient}}{{{clientName}}}{{/isCompositionClient}}{{#isCompositionClient}}compositionClient{{/isCompositionClient}}(process.env.ALGOLIA_APPLICATION_ID, process.env.{{e2eApiKey}}){{^isStandaloneClient}}.{{{initMethod}}}({{#hasRegionalHost}} {region:'{{{defaultRegion}}}'} {{/hasRegionalHost}}){{/isStandaloneClient}};
+const client = {{^isCompositionClient}}{{{clientName}}}{{/isCompositionClient}}{{#isCompositionClient}}compositionClient{{/isCompositionClient}}(process.env.{{e2eAppID}}, process.env.{{e2eApiKey}}){{^isStandaloneClient}}.{{{initMethod}}}({{#hasRegionalHost}} {region:'{{{defaultRegion}}}'} {{/hasRegionalHost}}){{/isStandaloneClient}};
 
 {{#blocksE2E}}
 describe('{{operationId}}', () => {
diff --git a/templates/kotlin/tests/e2e/e2e.mustache b/templates/kotlin/tests/e2e/e2e.mustache
index b463c673e0..12a66463b4 100644
--- a/templates/kotlin/tests/e2e/e2e.mustache
+++ b/templates/kotlin/tests/e2e/e2e.mustache
@@ -21,10 +21,10 @@ class {{clientPrefix}}Test {
 
     init {
       if (System.getenv("CI") == "true") {
-        this.client = {{client}}(appId = System.getenv("ALGOLIA_APPLICATION_ID"), apiKey = System.getenv("{{e2eApiKey}}"){{#hasRegionalHost}}, region = "{{defaultRegion}}", {{/hasRegionalHost}});
+        this.client = {{client}}(appId = System.getenv("{{e2eAppID}}"), apiKey = System.getenv("{{e2eApiKey}}"){{#hasRegionalHost}}, region = "{{defaultRegion}}", {{/hasRegionalHost}});
       } else {
         val dotenv = Dotenv.configure().directory("../../").load()
-        this.client = {{client}}(appId = dotenv["ALGOLIA_APPLICATION_ID"], apiKey = dotenv["{{e2eApiKey}}"]{{#hasRegionalHost}}, region = "{{defaultRegion}}", {{/hasRegionalHost}});
+        this.client = {{client}}(appId = dotenv["{{e2eAppID}}"], apiKey = dotenv["{{e2eApiKey}}"]{{#hasRegionalHost}}, region = "{{defaultRegion}}", {{/hasRegionalHost}});
       }
     }
 
diff --git a/templates/php/tests/e2e/e2e.mustache b/templates/php/tests/e2e/e2e.mustache
index b801725c77..a7e970bc88 100644
--- a/templates/php/tests/e2e/e2e.mustache
+++ b/templates/php/tests/e2e/e2e.mustache
@@ -17,7 +17,7 @@ use Psr\Http\Message\RequestInterface;
 use Dotenv\Dotenv;
 
 // we only read .env file if we run locally
-if (getenv('ALGOLIA_APPLICATION_ID')) {
+if (getenv('{{e2eAppID}}')) {
     $_ENV = getenv();
 } else {
     $dotenv = Dotenv::createImmutable('tests');
@@ -44,7 +44,7 @@ class {{clientPrefix}}Test extends TestCase
 
     protected function getClient(): {{client}}
     {
-        return {{client}}::create($_ENV['ALGOLIA_APPLICATION_ID'], $_ENV['{{e2eApiKey}}']{{#hasRegionalHost}},'{{defaultRegion}}' {{/hasRegionalHost}});
+        return {{client}}::create($_ENV['{{e2eAppID}}'], $_ENV['{{e2eApiKey}}']{{#hasRegionalHost}},'{{defaultRegion}}' {{/hasRegionalHost}});
     }
 
     {{#blocksE2E}}
diff --git a/templates/python/tests/e2e/e2e.mustache b/templates/python/tests/e2e/e2e.mustache
index cd71c3097f..8dfcfb7ccb 100644
--- a/templates/python/tests/e2e/e2e.mustache
+++ b/templates/python/tests/e2e/e2e.mustache
@@ -16,9 +16,9 @@ load_dotenv("../../.env")
 {{#modes}}
 class Test{{#lambda.pascalcase}}{{{client}}}{{/lambda.pascalcase}}{{#isSyncClient}}Sync{{/isSyncClient}}E2E:
     _helpers = Helpers()
-    _e2e_app_id = environ.get("ALGOLIA_APPLICATION_ID")
+    _e2e_app_id = environ.get("{{e2eAppID}}")
     if _e2e_app_id is None:
-        raise Exception("please provide an `ALGOLIA_APPLICATION_ID` env var for e2e tests")
+        raise Exception("please provide an `{{e2eAppID}}` env var for e2e tests")
 
     _e2e_api_key = environ.get("{{e2eApiKey}}")
     if _e2e_api_key is None:
diff --git a/templates/ruby/tests/e2e/e2e.mustache b/templates/ruby/tests/e2e/e2e.mustache
index 5b4880740e..a3f418b7db 100644
--- a/templates/ruby/tests/e2e/e2e.mustache
+++ b/templates/ruby/tests/e2e/e2e.mustache
@@ -9,7 +9,7 @@ Dotenv.load('../../.env')
 class Test{{#lambda.pascalcase}}{{{client}}}{{/lambda.pascalcase}}E2E < Test::Unit::TestCase
   def setup
     @client = Algolia::{{#lambda.pascalcase}}{{{client}}}{{/lambda.pascalcase}}.create(
-      ENV.fetch('ALGOLIA_APPLICATION_ID', nil),
+      ENV.fetch('{{e2eAppID}}', nil),
       ENV.fetch('{{e2eApiKey}}', nil){{#hasRegionalHost}},
       '{{{defaultRegion}}}'{{/hasRegionalHost}}
     )
diff --git a/templates/scala/tests/e2e/e2e.mustache b/templates/scala/tests/e2e/e2e.mustache
index cd408fc424..6bbbbf5e61 100644
--- a/templates/scala/tests/e2e/e2e.mustache
+++ b/templates/scala/tests/e2e/e2e.mustache
@@ -26,14 +26,14 @@ class {{clientPrefix}}TestE2E extends AnyFunSuite {
     {{/hasRegionalHost}}
     if (System.getenv("CI") == "true") {
       {{client}}(
-        appId = System.getenv("ALGOLIA_APPLICATION_ID"),
+        appId = System.getenv("{{e2eAppID}}"),
         apiKey = System.getenv("{{e2eApiKey}}"){{#hasRegionalHost}},
         region = region{{/hasRegionalHost}}
       )
     } else {
       val dotenv = Dotenv.configure.directory("../../").load
       {{client}}(
-        appId = dotenv.get("ALGOLIA_APPLICATION_ID"),
+        appId = dotenv.get("{{e2eAppID}}"),
         apiKey = dotenv.get("{{e2eApiKey}}"){{#hasRegionalHost}},
         region = region{{/hasRegionalHost}}
       )
diff --git a/templates/swift/tests/e2e/e2e.mustache b/templates/swift/tests/e2e/e2e.mustache
index 0d6b724cbf..ad9ef58166 100644
--- a/templates/swift/tests/e2e/e2e.mustache
+++ b/templates/swift/tests/e2e/e2e.mustache
@@ -35,9 +35,9 @@ final class {{client}}RequestsTestsE2E: XCTestCase {
       }
 
       do {
-          APPLICATION_ID = try XCTUnwrap(ProcessInfo.processInfo.environment["ALGOLIA_APPLICATION_ID"])
+          APPLICATION_ID = try XCTUnwrap(ProcessInfo.processInfo.environment["{{e2eAppID}}"])
       } catch {
-          XCTFail("Please provide an `ALGOLIA_APPLICATION_ID` env var for e2e tests")
+          XCTFail("Please provide an `{{e2eAppID}}` env var for e2e tests")
       }
 
       do {
diff --git a/tests/.env.example b/tests/.env.example
index 8a310fc4ef..3590a282a3 100644
--- a/tests/.env.example
+++ b/tests/.env.example
@@ -1,3 +1,7 @@
 ALGOLIA_APPLICATION_ID=
 ALGOLIA_ADMIN_KEY=
+
 MONITORING_API_KEY=
+
+METIS_APPLICATION_ID=
+METIS_API_KEY=
\ No newline at end of file
diff --git a/tests/CTS/requests/composition/listCompositions.json b/tests/CTS/requests/composition/listCompositions.json
index aeddc5c455..0fe9de7c0c 100644
--- a/tests/CTS/requests/composition/listCompositions.json
+++ b/tests/CTS/requests/composition/listCompositions.json
@@ -11,6 +11,29 @@
     "request": {
       "path": "/1/compositions",
       "method": "GET"
+    },
+    "response": {
+      "statusCode": 200,
+      "body": {
+        "items": [
+          {
+            "objectID": "id1",
+            "description": "the first ever composition from the client",
+            "behavior": {
+              "injection": {
+                "main": {
+                  "source": {
+                    "search": {
+                      "index": "cts_e2e_small"
+                    }
+                  }
+                }
+              }
+            }
+          }
+        ],
+        "nbPages": 1
+      }
     }
   }
 ]