diff --git a/packages/playwright-core/src/cli/cli.ts b/packages/playwright-core/src/cli/cli.ts
index 7b99cf49dc..7f1f531c20 100755
--- a/packages/playwright-core/src/cli/cli.ts
+++ b/packages/playwright-core/src/cli/cli.ts
@@ -658,7 +658,7 @@ async function launchGridServer(factoryPathOrPackageName: string, port: number,
   factory.name = factory.name || factoryPathOrPackageName;
   const gridServer = new GridServer(factory as GridFactory, authToken, address);
   await gridServer.start(port);
-  console.log('Grid server is running at ' + gridServer.urlPrefix());
+  console.log('Grid server is running at ' + gridServer.gridURL());
 }
 
 function buildBasePlaywrightCLICommand(cliTargetLang: string | undefined): string {
diff --git a/packages/playwright-core/src/grid/gridServer.ts b/packages/playwright-core/src/grid/gridServer.ts
index ace6f1da58..053c5e8ccb 100644
--- a/packages/playwright-core/src/grid/gridServer.ts
+++ b/packages/playwright-core/src/grid/gridServer.ts
@@ -253,7 +253,8 @@ export class GridServer {
         return true;
       }
 
-      if (request.url!.startsWith('/registerAgent') || request.url!.startsWith('/registerWorker')) {
+      if (request.url!.startsWith(this._securePath('/registerAgent'))
+       || request.url!.startsWith(this._securePath('/registerWorker'))) {
         const params = new URL('http://localhost/' + request.url).searchParams;
         const agentId = params.get('agentId');
         return !!agentId && this._agents.has(agentId);
@@ -285,7 +286,7 @@ export class GridServer {
         return;
       }
 
-      if (request.url?.startsWith('/registerAgent')) {
+      if (request.url?.startsWith(this._securePath('/registerAgent'))) {
         const params = new URL('http://localhost/' + request.url).searchParams;
         if (params.get('pwVersion') !== this._pwVersion) {
           ws.close(WSErrors.AGENT_PLAYWRIGHT_VERSION_MISMATCH.code, WSErrors.AGENT_PLAYWRIGHT_VERSION_MISMATCH.reason);
@@ -302,7 +303,7 @@ export class GridServer {
         return;
       }
 
-      if (request.url?.startsWith('/registerWorker')) {
+      if (request.url?.startsWith(this._securePath('/registerWorker'))) {
         const params = new URL('http://localhost/' + request.url).searchParams;
         const agentId = params.get('agentId')!;
         const workerId = params.get('workerId')!;
@@ -332,7 +333,7 @@ export class GridServer {
     const initPromise = Promise.resolve()
         .then(() => this._factory.launch({
           agentId: agent.agentId,
-          gridURL: this.urlPrefix(),
+          gridURL: this.gridURL(),
           playwrightVersion: getPlaywrightVersion(),
         })).then(() => {
           this._log('created');
@@ -386,8 +387,8 @@ export class GridServer {
     await this._server.start(port);
   }
 
-  urlPrefix(): string {
-    return this._server.urlPrefix() + this._securePath('/');
+  gridURL(): string {
+    return this._server.urlPrefix() + this._securePath('');
   }
 
   async stop() {
diff --git a/packages/playwright-test/src/cli.ts b/packages/playwright-test/src/cli.ts
index bd44754533..e65f37ac24 100644
--- a/packages/playwright-test/src/cli.ts
+++ b/packages/playwright-test/src/cli.ts
@@ -242,7 +242,7 @@ async function launchDockerContainer(): Promise<() => Promise<void>> {
   const { error } = await gridServer.createAgent();
   if (error)
     throw error;
-  process.env.PW_GRID = gridServer.urlPrefix().substring(0, gridServer.urlPrefix().length - 1);
+  process.env.PW_GRID = gridServer.gridURL();
   return async () => await gridServer.stop();
 }