test-data-mocking-mcp

An MCP server that mocks payments, third-party API responses, and test data — so QA flows for donation/checkout/SIP/subscription pages never depend on a live Razorpay (or any other) gateway.

This is the first piece of the AI Test Orchestration platform (see the proposal doc) — it directly unblocks the post-payment pages (/payment-success, /enrolment, /slot-booking, /thankyou) that are currently gated behind a live gateway in the QA Agent.

Tools exposed

Related MCP server: MCP Cypress Page Object Generator

⚠️ Signature verification — read this before wiring into a real backend

mock_payment returns a razorpay_signature field shaped like a real one, but it is random bytes, not a real HMAC — it cannot pass real Razorpay signature verification, because that requires your live merchant secret, which this server intentionally never touches.

This tool is built to unblock UI/flow testing of post-payment pages (does the success page render correctly, does the thank-you email trigger, does the enrolment flow advance) — not to bypass real signature checks in a production code path. If your backend's payment-verification endpoint enforces signature checks even in a test environment, add a test-mode bypass there that recognizes IDs prefixed pay_test_ / order_test_ and skips HMAC verification for those. That's a one-line check in your verification middleware, not something this MCP server can or should do for you.

Run locally

npm install
npm start
# Health check: http://localhost:8787/health
# MCP endpoint:  http://localhost:8787/mcp

Quick manual test with curl:

curl -s -X POST http://localhost:8787/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-06-18","capabilities":{},"clientInfo":{"name":"test","version":"1.0.0"}}}'

Deploy to Railway

Same pattern as the Mixpanel monitor — push this repo, connect it as a new Railway service, no extra config needed beyond the default Node buildpack. Railway sets PORT automatically; src/index.js already reads process.env.PORT.

git init
git add .
git commit -m "Test Data Mocking MCP — payments, API, and entity mocks"
git remote add origin <your-new-repo-url>
git push -u origin main

Then in Railway: New Project → Deploy from GitHub repo → select this repo. No environment variables are required for v1 since nothing here touches real secrets.

Wiring it into n8n

In an n8n workflow, use an HTTP Request node pointed at https://<your-railway-url>/mcp with the JSON-RPC body shown above, or use n8n's MCP Client node if you're on a version that has it — point it at the same URL. Either way, this server is stateless, so you don't need to manage sessions between calls; every request is self-contained.

Wiring it into the QA Agent backend or any AI agent

Add it as an MCP server the same way Asana/ClickUp/Slack are configured — point at the deployed /mcp URL. Any agent (Suite Creation Agent, Execution Agent, or a one-off test script) can then call mock_payment, generate_test_user, etc. as ordinary tools.

Project structure

test-data-mocking-mcp/
├── package.json
├── src/
│   ├── index.js        # Express app, stateless Streamable HTTP transport
│   ├── server.js        # MCP server + all 6 tool registrations
│   └── mocks/
│       ├── payment.js   # mock_payment logic
│       ├── api.js       # mock_api_response logic
│       └── testData.js  # generate_test_* logic
└── README.md

What's next

Per the build sequence: Smart Suite Generator (#2), Structured RCA / Failure Analysis Agent (#3), then the DB schema migration (#4). This server doesn't need to change for those — it's a standalone, finished piece.