UI Blackbox Tester MCP — natural-language UI testing for Claude Desktop via Playwright
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# UI Blackbox Tester MCP **🌐 Language:** **English** · [한국어](./README.ko.md) > **Test your UI in plain language — an MCP server.** Give Claude Desktop (and other > MCP clients) the ability to drive a browser. Say *"check that the login flow works"* > and the agent opens a browser, clicks, types, asserts, and leaves a **QA report > (HTML/MD/JSON)** behind — no test code required. <p align="center"> <img src="examples/sample_report_preview.png" alt="Sample report" width="620"> <br><em>Auto-generated report — pass rate · per-step screenshots · failure cause · regression · accessibility · credential masking</em> </p> [](https://pypi.org/project/ui-blackbox-mcp/) [](https://pypi.org/project/ui-blackbox-mcp/) Python 3.11+ · Playwright (Chromium, async) · official MCP SDK (FastMCP) · stdio · **tests green in CI** --- ## ✨ What's different (vs a generic browser MCP) Plenty of tools can drive a browser. This one is built around the **QA workflow**. | | Generic browser MCP | **UI Blackbox MCP** | |---|---|---| | Authoring | Write selectors by hand | **Natural language → kit → reusable scenario** (`generate_scenario`) | | Reuse | Start over each time | **Save & load by name** (scenario library) | | Output | Text / logs | **QA report**: pass rate · step screenshots · **AI failure cause + fix suggestion** · **regression diff** · **a11y findings** · severity | | Selector stability | Breaks every build | **D2 priority chain** (data-testid → role+name → text → css) + `resolved_by` transparency | | Security | — | **Credential masking** (`${VAR}` injected from env, never written to reports) | → Not a developer tool, but **regression-test automation that non-developer QA/PMs can drive in natural language**. --- ## 🚀 Quick start ### 1) Install **Option A — from PyPI, no clone (recommended).** `uvx` (Python's `npx`; ships with [uv](https://docs.astr…
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