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muhammad Sanaev
muhammad Sanaev

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Stop Letting AI Guess Your Playwright Tests: Use Context7 MCP

The problem

While working on my Swiftcart QA automation project, I asked my AI agent a simple question:

“What’s your knowledge cutoff date?”

It answered: April 2024.

That matters because Playwright changes fast. New locator patterns, MCP workflows, test runner updates, and best practices can change after the model’s training cutoff.

AI agent cutoff date screenshot

What Context7 MCP is

Context7 - Up-to-date documentation for LLMs and AI code editors

Pull up-to-date, version-specific documentation and code examples for any library directly into Cursor, Claude Code, Windsurf, and other AI coding tools.

favicon context7.com

Context7 MCP is a documentation server for AI coding assistants.

Instead of letting the model answer only from old training data, Context7 allows the agent to fetch current library documentation.

For my workflow, I used it with:

  • Cursor
  • Playwright
  • Context7 MCP
  • Playwright MCP
  • Swiftcart demo app

Why this matters for QA automation

AI can generate tests quickly, but it may also:

  • suggest outdated syntax
  • hallucinate APIs
  • create brittle locators
  • miss current Playwright best practices
  • generate tests that pass but don’t test the right thing

Context7 does not replace knowing Playwright. It gives the AI better context.

How I connected Context7 MCP

In my project, I created:

.vscode/mcp.json

{
  "servers": {
    "context7": {
      "command": "npx",
      "args": ["-y", "@upstash/context7-mcp"]
    }
  }
}
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Confirmation
After restarting Cursor, I asked the agent:

Use Context7 MCP specifically.
Do not use web search.
Resolve the Playwright library ID, then fetch locator docs.
List the exact Context7 tool names used.

A good sign is seeing tools like:

context7: resolve-library-id
context7: query-docs

Swiftcart app

Playwright MCP inspects the real page

Context7 MCP provides current Playwright docs

Cursor generates the first test draft

I review locators and assertions

Final tests run with Playwright CLI

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