How Stably Works
Stably has 3 connected products that work seamlessly together.1. Stably Playwright SDK
Drop-in replacement for@playwright/test that adds AI runtime capabilities.
- AI Assertions & Extraction – verify dynamic UIs (charts, PDFs, canvas) with natural-language intent and structured data extraction.
- Auto-Heal – automatically repairs locators, visuals, or regenerates steps when UI changes.
- Agent Actions – execute multi-step AI commands (
agent.act(...)) for dynamic or stateful flows. - Built-in Caching – AI runs only when your UI meaningfully changes; otherwise runs deterministic cached steps.
- 100% Playwright-compatible – same CLI, fixtures, reporters, and CI setups.
2. No-Code Tests (AI Editor + Cloud Runner)
Create, edit, and run tests without code — then export to Playwright anytime.- Generate or record tests in plain English with an interactive editor.
- Supports variables, conditionals, and reusable components.
- Handles advanced UX like charts, canvas, and file upload/download flows.
- Auto-heal and caching built-in for stability and cost control.
- Cloud runner executes in parallel with full traces and screenshots.
- One-click export to your Playwright repo for deeper CI integration.
Author tests with an interactive editor. Export to Playwright.
3. Triage & Auto-Heal Agent
When a test fails, Stably’s Triage Agent performs full root-cause analysis.- Scans all Playwright traces, console logs, and network data.
- Cross-references your source repo to detect:
- 🐞 Real product bug
- 🧪 Test needing update
- ⚙️ Infrastructure or flake
- Generates an AI repair prompt you can paste into Cursor, Claude Code, or Copilot.
Why Stably?
- More Coverage — test dynamic UX like charts, graphs, and canvas that static assertions miss.
- Fewer Flakes — auto-heal and caching keep suites green and deterministic.
- Faster Authoring — create tests faster with AI-assisted authoring and repair.
- Workflow Fit — same Playwright commands and CI setup; optional dashboard only.
Trusted by Builders
Backed by Y Combinator and Vercel Ventures, Stably is used by hundreds of fast-growing teams.The founding team previously built infrastructure at Google Chrome and Uber.
Next Steps
- SDK Quickstart — install the SDK and run your first AI assertion.
- No-Code Editor — author tests visually, then export to Playwright.