Load Testing with AI

Connect Claude, ChatGPT, or Cursor to your Loadster account. Your assistant writes the scripts, builds the test scenarios, runs the load test, and explains the results. Load test with thousands of concurrent Playwright, Browser Bots, or Protocol Bots from 32 AWS and GCP cloud regions in less time than ever.

Loadster's MCP server lets your favorite AI assistant work inside your account. It uses 50+ tools to write and validate scripts, assemble scenarios, launch and watch tests, and read the results. You choose how far it goes when you connect it.

Accelerate your load testing with a little help from AI. Scripting, test setup, and the test itself are now just a quick chat session.

can you write a loadster script for our checkout flow? staging site is staging.acmeoutfitters.com. go to the homepage, search for "trail shoes", add the first result to the cart, and check out as a guest. use a real browser

I'll build this as a Browser Bot script so it drives real Chrome the way a shopper would. Let me read Loadster's browser scripting docs first, then create the script and play it once before handing it over.

get_documentation browser-scripts create_script "Guest Checkout" play_script

The first play got through search and add-to-cart but failed at checkout: the "Continue as guest" button never became clickable. The screenshot shows a cookie banner sitting on top of it, so I'll add a step to dismiss the banner and play it again.

get_screenshot update_script play_script

That fixed it. All 7 steps pass in about 9 seconds, and the confirmation page renders with an order number. The script is saved in your Staging project: Guest Checkout ↗. Want me to add a dataset of shipping addresses so each bot checks out with different details?

yeah do the addresses. then lets run a real load test. 1000 bots split between virginia and london, ramp up fast, hold for 5 min

Done. I created a dataset with 250 shipping addresses, wired it into the checkout step, and re-played the script to confirm it still passes.

create_dataset "Shipping addresses" update_script play_script list_engines create_scenario "Guest checkout 1000 browsers"

The scenario is built:

  • 500 Browser Bots from N. America - Virginia, 500 from Europe - United Kingdom
  • Ramp to 1,000 in 60 seconds, hold for 5 minutes, then ramp down over 30 seconds

It's ready here: Guest checkout 1000 browsers ↗. The estimate is 434 to 450 units of fuel, and you have 2,400. Want me to launch it?

looks good, launch it 🚀
launch_load_test get_load_test_status

It's running, and all 1,000 bots are up. The 95th percentile is 1.8 seconds from Virginia but 4.1 seconds from London, and engine CPU is under 40% in both regions, so the slowdown is your site, not the load generators. I'll keep an eye on it and read the report when it finishes.

Your AI assistant is now your performance engineer. Write and play scripts, build datasets, run load tests, and analyze results.

Loadster's MCP server gives your assistant access to scripts, datasets, scenarios, reports, and monitors. MCP changes affect the same project data your teammates see, so review your assistant's proposed changes just as you would in the dashboard.

You choose how far it goes when you connect it. At Read, it can look but not change anything. At Read+Write, it builds scripts, scenarios, and monitors and leaves the launch to you. At Read+Write+Execute, it can also launch and stop load tests and enable monitors, telling you the fuel estimate and asking before it launches. Billing and your team always stay with you.

Capability Your AI assistant You
Scripting
Write and edit Protocol Bot, Browser Bot, and Playwright scripts✓✓
Import an existing JMeter, k6, or Locust test✓✓
Record a script with the browser extension–✓
Validate a script and play it as a single bot✓✓
Inspect step results, response bodies, and screenshots✓✓
Roll back to an earlier script revision✓✓
Datasets and scenarios
Create and fill datasets✓✓
Build scenarios with populations, ramps, and regions✓✓
Load tests
Launch a load test (with execute access)✓✓
Follow a running load test live: bots, response times, errors, and engine CPU✓✓
Stop a running load test (with execute access)✓✓
Read the test report and explain what happened✓✓
Add notes to a test report✓✓
Monitoring
Create and configure monitors✓✓
Enable a monitor (with execute access)✓✓
Disable a monitor✓✓
Investigate incidents and monitor cycles✓✓
Notification policies and maintenance windows–✓
Account
Team members, billing, and fuel–✓
Connect Your AI Assistant

Automate real headless Chrome browsers or lightweight HTTP clients. AI-assisted scripting with your choice of Playwright, Browser Bots, or Protocol Bots.

Browser Bot

Browser Bots

Record scripts in your browser with Loadster's free extension and edit them visually. Add JavaScript if necessary. Browser Bots automate real headless Chrome browsers for realistic web application testing with a minimal learning curve.

Scripting style
Visual or JavaScript
Good for testing
Web Applications, Modern Websites
Fuel consumption
4× per bot-hour
Browser Bot Scripts
Protocol Bot

Protocol Bots

Protocol Bots execute scripted HTTP/S requests against your API or static website. Testing at the protocol layer is cost-effective and easily scales to hundreds of thousands of concurrent bots, and is ideal for testing HTTP APIs at scale.

Scripting style
Visual or JavaScript
Good for testing
APIs, Simple Websites
Fuel consumption
1× per bot-hour
Protocol Bot Scripts
Playwright Bot

Playwright

Run your Playwright Test scripts at scale through Loadster's cloud. Ideal for teams already using Playwright or who want programmatic control with an open source testing framework, combined with Loadster's cloud scaling and reporting.

Scripting style
JavaScript/TypeScript
Good for testing
Web Applications, Modern Websites
Fuel consumption
4× per bot-hour
Playwright Scripts

Bring your own AI assistant. Loadster MCP opens the load testing platform to Claude, ChatGPT, Cursor, and other leading AI assistants.

Loadster uses MCP (Model Context Protocol), an open standard for connecting AI assistants to external tools. Clients with OAuth support can send you to Loadster to approve the connection in your browser, with no token to copy. Clients without OAuth, along with CI jobs and scripted agents, can use a personal access token instead, which you create under Settings → API & MCP → Personal Access Tokens.

Once connected, your AI assistant acts on your behalf in Loadster, and you can see and revoke its access anytime on the API & MCP page in your Loadster settings. In ChatGPT and Codex, you can also install Loadster as an official plugin straight from the plugin directory. The MCP manual page has steps for ChatGPT, Codex, Claude Code, Cursor, VS Code, Claude Desktop, and other MCP clients.

Already having an assistant write k6 or JMeter scripts to run yourself? That works for small tests, and Why use Loadster if AI can write my k6 or JMeter script? covers what changes at scale.

Connect to the Loadster MCP server

Install the Loadster plugin, which adds the MCP server and a few load testing skills:

/plugin marketplace add loadster/loadster-mcp
/plugin install loadster@loadster

Then run /mcp, choose loadster, and approve the Loadster OAuth connection in your browser. To add just the server instead, run claude mcp add --transport http loadster https://api.loadster.com/mcp.

Claude Code setup guide »

Any other MCP client that supports remote servers over Streamable HTTP connects to the same URL, with OAuth or a personal access token. 

https://api.loadster.com/mcp

Setup guides for every client »

Create Your Free Account

Load testing results without the endless configuration. Loadster's cloud testing platform helps you move faster: browser-based script recording, live test metrics, automatic reports.

1

Record test scripts

Record load test scripts right in your browser with the Loadster Recorder extension for Chrome or Firefox. Just navigate your site like a real user, while Loadster automatically records every action into a reusable test script.

2

Edit and replay scripts

Play scripts as often as you like in Loadster's script editor. Bots execute your script and give you immediate real-time feedback. In the editor you can add, edit, and replace steps from the recording, or you can even build a script from scratch.

3

Configure test scenarios

A scenario is a reusable configuration for a load test. You'll specify the number of bots in each group, the AWS or GCP regions bots will run from, which of your scripts to execute, and the schedule for ramping the load up and down.

4

Launch your load test

When you launch a load test from a scenario, Loadster quickly spins up cloud resources to power your bots. Tests usually start in about 2-3 minutes, using fully managed infrastructure through Loadster's AWS and GCP cloud providers.

5

Observe real-time results

While a load test runs, your bots report real-time metrics to Loadster, and Loadster surfaces the latest details and diagnostics within seconds. Keep tabs on response times, throughput, errors, and detailed traces so you can see how your site is performing under load.

6

Generate test reports

After a load test finishes, Loadster automatically creates a detailed report so you can review your site's performance and scalability. This includes detailed graphs showing response times, errors, network and transaction throughput, and more. The report also includes detailed traces with request and response bodies or screenshots to help with troubleshooting.

7

Repeat and iterate

Load testing is an iterative process, and it's rare that everything goes perfectly on the very first try. After all, the point of the test is to discover scalability bottlenecks so you can fix them instead of crashing in production. With Loadster you can quickly re-test a previous scenario, or make changes to your scripts or scenarios and run again at any time.

Start Your Load Testing

Run load tests on demand from 32 AWS and GCP cloud regions. Monitor continuously from 8 locations across 5 continents.

Loadster Global Network 32 regions online
AWS GCP Monitoring

Loadster scales with your testing and your budget. Choose between flexible pay-as-you-go and a flat, predictable plan.

Pay As You Go

Starting at $97 for 1,000 units

Purchase as much Loadster Fuel as you need for your load testing and monitoring. No commitment, just buy fuel when you need it.

Check Fuel Pricing

Loadster Team

$499 a month, billed annually

Load testing and monitoring for the whole team at a flat, predictable price. All-inclusive testing within your plan limits.

Check Team Pricing

Frequently Asked Questions

Can I load test with an AI assistant like Claude, ChatGPT, or Cursor?
Yes. Loadster runs an MCP (Model Context Protocol) server, so assistants like Claude, ChatGPT, and Cursor can connect to your account and write scripts, build load test scenarios, set up monitors, and analyze results. You describe the flow you want to test, and the assistant builds it in your project with the same tools you’d use. Depending on the access level you choose when you connect it, it can launch the test and follow it live too, or hand you a scenario that’s ready to launch.
What is the Loadster MCP server?
It’s a built-in Model Context Protocol server for the Loadster testing platform. MCP is an open standard that lets AI assistants call external tools, and Loadster’s MCP server exposes the script editor, load test scenarios, monitors, and results. Once you connect your assistant, it can work in your Loadster account on your behalf within your team.
Which AI assistants can connect to Loadster?
Any MCP client that supports remote servers over Streamable HTTP and can authenticate with OAuth or a bearer token. Claude (Claude Code and the desktop app), ChatGPT, Cursor, Codex, and VS Code are some common options, and ChatGPT and Codex can install Loadster as an official plugin from their plugin directory. Setup for each client is in the Loadster manual.
Can the AI actually launch a load test?
Yes, if you let it. When you connect an assistant, you choose its access level. At “Read+Write+Execute”, it can launch a load test, follow it live, and stop it, and it tells you the fuel estimate and asks before launching. At the lower levels, it builds a ready-to-run scenario and gives you a dashboard link to launch it yourself.
Do I need to know scripting to load test with AI?
Not to get started. You can describe the user flow in plain language and let the assistant write the script, then review and adjust it. Scripting is often the slowest part of load testing, so this is a quick way to go from an idea to a working test, even if you’re not yet comfortable writing scripts by hand.

Loadster has optimized the performance, scalability, and uptime of thousands of sites. We're proud to be a testing platform of choice to elite teams.

  • Nginx
  • Wells Fargo
  • Amazon
  • Queensland Government
  • Accenture
  • Yale University
  • HBO
  • Mint Mobile
  • KPMG
  • Perficient
  • Dell
  • Pearson

Move fast
Don’t crash

Ready to cut your risk of downtime? Load test to prevent crashes. Monitor to react quickly.

Start Load Testing