Purpose-built for developers working with coding agents
Testing tools like Playwright and Cypress tell you a test failed, but they don’t tell you why it failed at the system level and they don't automatically fix it.
Multiplayer sits at the layer below your test suite: when a test fails, Multiplayer has already captured the full-stack, unsampled session data around that failure, pre-correlated across service boundaries. That data goes directly to your coding agent, to write the fix and open a PR. The feedback loop goes from "test failed, go investigate" to "test failed, PR ready for review.”
The perfect companion for coding agents
Multiplayer runs locally next to your favorite coding agent and captures full-stack session data (including the data observability tools miss!) only when something goes wrong.
Multiplayer can run in any environment — dev, QA, staging, prod — so it catches failures the moment tests surface them, before the code ever ships.
Key benefits for test debugging
Using Multiplayer results in what developers actually want from AI-assisted development:
Works seamlessly with your existing test stack
Keep your current setup (Cypress, Playwright, Selenium, Puppeteer) and add the missing layer of visibility. Multiplayer integrates alongside your testing tools to show why tests fail and automatically fix them, eliminating guesswork and cutting mean time to resolution.
Accelerated root cause analysis
Everything needed to understand the test failure is in one place, pre-correlated in a single timeline. This means less manual investigation time for you and fewer tokens burned on your coding agent grepping through unrelated data.
Catch quality issues you would otherwise miss
No testing suite is bulletproof. Transient failures, session-specific edge cases, and bugs that only surface under specific production conditions rarely show up in QA. Multiplayer monitors continuously and captures them anyway, unsampled, the moment a session reveals them.
No vendor lock-in, no bloated bills
Multiplayer is plug and play with any coding agent: Claude Code, Codex, Copilot, Cursor. When a better or cheaper model ships, you switch without rebuilding your tech stack. Built on OpenTelemetry and available as open source, with a session-based data model that means you're sending exactly what your coding agent needs, and nothing more.
Interactive notebooks for regression testing
Full-stack session recordings automatically convert into interactive notebooks that enable QA and developers to:
- Generate immediate test scripts for regression testing
- Create live fix testing environments
- Execute API calls and code snippets directly from the notebook
- Chain APIs and code in sequence for validation
- Document test failures and intended behavior
- Share reproducible debugging scenarios across teams