Karate API Test Generator for VS Code

The complete Karate DSL toolkit — Generate, execute, maintain, and analyze API tests with AI assistance.

Transform OpenAPI specs, Postman collections, and Confluence docs into production-ready Karate tests in seconds. Run them from your editor, track coverage, and let AI keep everything in sync as your API evolves.

Keywords: Karate API testing, OpenAPI test generation, API automation, Karate DSL, REST API testing, BDD API tests, QA automation, contract testing, Postman to Karate converter

🆕 What's New in v1.3.5

🧠 Agent Skills & Prompt Hardening

• Grounded AI Generation: Copilot now uses a dedicated knowledge base of Karate best practices to generate code.
• Zero Hallucination: Strict scoping rules ensure AI only uses endpoints and fields that actually exist in your API spec.
• 4 Bundled Skills: Includes guides for karate-dsl-reference, test-patterns, anti-patterns, and reusability.

🎯 Precision Controls UI

• Fine-Grained Filtering: Select exactly which Scenario Types (Positive, Negative, Edge, Security) and HTTP Methods you want to generate.
• Custom Instructions: Provide free-text guidance to Copilot for specific requirements (e.g., "Use tenantId header for all requests").

🏗️ Feature Structuring Engine

• Domain-Driven Organization: Automatically groups tests into separate feature files based on your API's domain or tags.
• 3 Structuring Strategies:
  • Domain (default): Group by tag/resource (e.g., orders.feature, users.feature).
  • Flat: All scenarios in one file.
  • Method: Group by HTTP method.

♻️ Smart Reusability Engine

• Auto-Extraction: Detects repeated patterns (auth, setup, headers) and extracts them into reusable common/ feature files.

• Intelligent Stubs: Auto-creates common/setup.feature, common/auth.feature etc. with functional defaults if they don't exist.

• Internal code quality improvements, security hardening, and test infrastructure updates.

🚀 Previously in v1.3.3

🔍 Universal Config Discovery

• Workspace-Wide Search: Automatically finds karate-config.js and runner classes anywhere in your project — no more hardcoded paths.
• LLM-Powered Suggestions: Copilot suggests optimal classpath and JVM args based on your project structure.

⚙️ Custom Execution Parameters

Three new settings let you control exactly how tests run:

📥 HAR File Import

• One-Click Import: Convert .har files from browser DevTools into Karate feature files.
• AI Enhancement: Copilot enriches imported requests with assertions and error scenarios.

⚡ Why Karate API Test Generator?

Stop wasting hours manually writing Boilerplate Gherkin. Let AI handle the structure so you can focus on business logic.

✨ Features at a Glance

🤖 AI-Powered Test Generation

Generate tests from three input sources, each enhanced by GitHub Copilot:

• OpenAPI / Swagger — Right-click any .json, .yaml, or .yml spec → Generate Tests Now
• Confluence Documentation — Pull API docs from Confluence pages and generate tests
• Combined (OpenAPI + Confluence) — Merge spec structure with documentation context for the richest tests

Copilot adds: smart assertions, realistic test data, edge-case scenarios (400, 401, 404, 500), and performance tests.

🧪 Native Test Executor

Run Karate tests directly from VS Code — no terminal required.

• CodeLens Actions: Click ▶ Run Feature or ▶ Run Scenario inline in .feature files
• Testing Sidebar: All features and scenarios appear in the VS Code Testing tab
• Auto-Discovery: Every .feature file in your workspace is detected automatically
• Build Tool Support: CLI (standalone JAR), Maven, or Gradle — auto-detected or configurable

📊 Premium Execution Dashboard

A modern, interactive dashboard replaces plain-text reports.

• Visual Analytics: Donut charts for pass/fail rates, bar charts for duration
• Feature Drill-Down: Expand any feature to inspect scenarios and step-level details
• Search & Filter: Find failing tests instantly
• Dark Mode: Full VS Code theme support with glassmorphism effects

📈 Visual Test Coverage

Track which API endpoints have tests and which don't.

• Coverage Dashboard: See tested vs untested endpoints at a glance
• Gap Analysis: Identify missing test scenarios per endpoint
• Generate Missing Tests: Click to generate tests for uncovered endpoints
• Append to Existing Files: Add AI-generated scenarios to existing feature files with matching style

📦 Postman Collection Import

Migrate from Postman to Karate in one click.

• Full Collection Conversion: Collections + environments → Karate feature files
• Variable Translation: Postman {{variables}} become Karate karate.properties
• Script Conversion: Pre-request scripts and test assertions converted via Copilot

📥 HAR File Import

Convert real API traffic into Karate tests.

• Browser DevTools: Export a .har file from Chrome/Firefox DevTools → import into the extension
• AI Enhancement: Copilot analyzes requests and generates assertions, schema checks, and error scenarios
• Selective Import: Choose which requests to convert — filter by domain, method, or status code

🔄 Automatic Test Maintenance

When your OpenAPI spec changes, the extension keeps tests in sync.

1. Detects changes when you save the spec
2. Analyzes impact on existing test files
3. Uses Copilot to intelligently update affected tests
4. Preserves custom logic you've added manually

🩺 Project Health Doctor

Real-time code quality analysis for Karate projects.

• Linter: Catches errors as you type — hardcoded URLs, duplicate scenarios, indentation issues
• Security Scanner: Detects missing auth tests and hardcoded secrets
• Quick Fixes: One-click auto-fixes for common issues
• Health Dashboard: Visualize project structure and dependencies

🎨 Style Learning

Maintain consistency across your team's tests.

• Learn from Examples: Right-click a well-formatted .feature file → Learn Style Now
• Future Consistency: All generated tests match your team's patterns
• Template System: Save and reuse preferred test structures

🛡️ Copilot Transparency & Privacy

Full visibility into AI interactions.

• Activity Log: View every prompt and response (Cmd+Shift+P → Show Copilot Activity Log)
• Privacy: Sensitive data (API keys, tokens) is automatically redacted
• Performance Metrics: See response times and token usage

🚀 Quick Start

1. Install

Search for "Karate Test Generator" in the VS Code Extensions marketplace, or install from the Marketplace page.

2. Generate Your First Test

Option A — Right-Click Menu (fastest):

1. Right-click any OpenAPI spec file (.json, .yaml, .yml)
2. Select Karate: Generate Tests Now
3. Click Open File to view the generated .feature file

Option B — Extension Panel:

1. Click the Karate icon in the Activity Bar
2. Navigate to the OpenAPI tab
3. Select your spec file and click Generate Tests

3. Run Tests

• Click ▶ Run Feature above the Feature: line in any .feature file
• Or open the Testing sidebar and click the play button

4. Enable AI Enhancement (optional)

1. Install the GitHub Copilot extension
2. Generate tests as usual — Copilot automatically enhances them with richer assertions and edge cases

📖 Usage Guide

Generating from OpenAPI

Right-click spec.yaml → "Karate: Generate Tests Now"

Or use the Extension Panel → OpenAPI tab with the Copilot toggle for AI-enhanced output.

Generating from Confluence

1. Open the Extension Panel → Confluence tab
2. Enter the Confluence page URL
3. Provide credentials (see Configuration below)
4. Click Generate Tests

Extracted content: API endpoint descriptions, request/response examples, business logic, edge cases.

Combined Generation (OpenAPI + Confluence)

1. Open the Extension Panel → Combined tab
2. Select the OpenAPI spec file
3. Enter the Confluence documentation URL
4. Click Generate Tests

Result: Tests combine the structure from your OpenAPI spec with the business context from your documentation.

Importing Postman Collections

Cmd+Shift+P → "Karate: Import Postman Collection"

Select your Postman collection file (.json) and optionally an environment file.

Running Tests

Learning Style

Right-click your best .feature file → "Karate: Learn Style Now"

All future generations will match this file's formatting, naming, and assertion patterns.

⚙️ Configuration

Access settings via Preferences → Settings and search for karateDsl.

Execution Settings

Confluence Settings

Copilot Settings

Agent Skills (VS Code 1.108+)

Agent Skills provide Karate-specific domain knowledge (syntax patterns, API testing best practices, conversion rules) to GitHub Copilot. Automatically enabled on VS Code 1.108+; gracefully disabled on earlier versions.

📝 Example Output

Input: OpenAPI spec with /pets/{id} endpoint

Generated Test:

Feature: Pet API Tests

  Background:
    * url baseUrl
    * def petId = 1

  Scenario: Get pet by ID - Success
    Given path 'pets', petId
    When method GET
    Then status 200
    And match response.id == petId
    And match response.name == '#string'

  Scenario: Get pet by ID - Not Found
    Given path 'pets', 99999
    When method GET
    Then status 404

🔧 Requirements

🐛 Troubleshooting

Tests not generating?

• Verify the file is a valid OpenAPI spec (JSON/YAML)
• Check the Output panel → Karate Test Generator for errors

Copilot not working?

• Ensure GitHub Copilot extension is installed and activated (check status bar)
• Verify you have an active Copilot subscription

karate.env not being applied?

• Set it in systemProperties, not as a separate environment setting:

  "karateDsl.execution.systemProperties": { "karate.env": "local" }
  

• Check Output panel for [DEBUG] User systemProperties: to confirm it's read

Config file not found?

• The extension searches your entire workspace. Check Output panel for discovery logs.
• Use karateDsl.execution.configPath to set an explicit path.

📚 Documentation

• Copilot Integration Guide
• Development Setup

📄 License

MIT License — see LICENSE for details.

🙏 Acknowledgments

• Built with Karate DSL
• Powered by GitHub Copilot
• OpenAPI parsing by @apidevtools/swagger-parser

💬 Feedback & Support

• 🐛 Report Issues
• 💡 Request Features
• ⭐ Star on GitHub

Made with ❤️ for the Karate testing community