Can I simulate specific API errors like 401 Unauthorized or 500 Internal Server Error?

Yes, the skill includes specific workflows to map endpoints to custom HTTP status codes and error bodies to test your application's error handling logic.

Does it support both REST and GraphQL APIs?

Yes. It intercepts requests at the network level (XHR/Fetch), making it compatible with any HTTP-based API architecture including REST and GraphQL.

Does this require a running backend to work?

No. While you can record real responses from a backend, the skill is designed to replay and modify those responses so you can test the frontend in complete isolation.

Can I use this to test loading spinners and timeouts?

Absolutely. You can apply artificial latency to specific endpoints or all API calls to verify how your UI handles slow network conditions.

Network Mock Server

Name: Network Mock Server
Author: anouar1991

byanouar1991

•

Security & Testing

Creates a flexible API mocking layer to intercept, record, and modify network requests for deterministic frontend testing.

The Network Mock Server skill provides a comprehensive toolkit for managing API interactions within Playwright-driven workflows. It allows developers to record live API responses as baselines, replay them to ensure consistent test environments, and inject custom logic to simulate edge cases like high latency, server errors, or specific data payloads. By abstracting backend dependencies, it enables robust frontend validation, loading state testing, and offline development without requiring a live or stable staging environment.

Key Features

01Replay intercepted requests deterministically with custom response bodies and headers

02Simulate network conditions like endpoint-specific latency and timeouts

03Test error handling by forcing specific HTTP status codes and error payloads

04Deep network control via CDP Fetch domain for low-level request interception

051 GitHub stars

06Record and harvest real API responses to create baseline data snapshots

Use Cases

01Simulating backend failures and slow network states to validate UX resilience

02Creating isolated, repeatable E2E test environments independent of live services

03Testing frontend UI behavior against complex or rare API response shapes

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add anouar1991/binarypetsclaude network-mock-server

For use in Claude.ai and ChatGPT

Download Skill