Polyglot Test Generation Skill

An AI-powered skill that generates comprehensive, workable unit tests for any programming language using a coordinated multi-agent pipeline.

When to Use This Skill

Use this skill when you need to:

Generate unit tests for an entire project or specific files

Improve test coverage for existing codebases

Create test files that follow project conventions

Write tests that actually compile and pass

Add tests for new features or untested code

How It Works

This skill coordinates multiple specialized agents in a

Research → Plan → Implement

pipeline:

Pipeline Overview

┌─────────────────────────────────────────────────────────────┐

│ TEST GENERATOR │

│ Coordinates the full pipeline and manages state │

└─────────────────────┬───────────────────────────────────────┘

│

┌─────────────┼─────────────┐

▼ ▼ ▼

┌───────────┐ ┌───────────┐ ┌───────────────┐

│ RESEARCHER│ │ PLANNER │ │ IMPLEMENTER │

│ │ │ │ │ │

│ Analyzes │ │ Creates │ │ Writes tests │

│ codebase │→ │ phased │→ │ per phase │

│ │ │ plan │ │ │

└───────────┘ └───────────┘ └───────┬───────┘

│

┌─────────┬───────┼───────────┐

▼ ▼ ▼ ▼

┌─────────┐ ┌───────┐ ┌───────┐ ┌───────┐

│ BUILDER │ │TESTER │ │ FIXER │ │LINTER │

│ │ │ │ │ │ │ │

│ Compiles│ │ Runs │ │ Fixes │ │Formats│

│ code │ │ tests │ │ errors│ │ code │

└─────────┘ └───────┘ └───────┘ └───────┘

Step-by-Step Instructions

Step 1: Determine the User Request

Make sure you understand what user is asking and for what scope.

When the user does not express strong requirements for test style, coverage goals, or conventions, source the guidelines from

unit-test-generation.prompt.md

. This prompt provides best practices for discovering conventions, parameterization strategies, coverage goals (aim for 80%), and language-specific patterns.

Step 2: Invoke the Test Generator

Start by calling the

polyglot-test-generator

agent with your test generation request:

Generate unit tests for [path or description of what to test], following the unit-test-generation.prompt.md guidelines

The Test Generator will manage the entire pipeline automatically.

Step 3: Research Phase (Automatic)

The

polyglot-test-researcher

agent analyzes your codebase to understand:

Language & Framework

Detects C#, TypeScript, Python, Go, Rust, Java, etc.

Testing Framework

Identifies MSTest, xUnit, Jest, pytest, go test, etc.

Project Structure

Maps source files, existing tests, and dependencies

Build Commands

Discovers how to build and test the project

Output:

.testagent/research.md

Step 4: Planning Phase (Automatic)

The

polyglot-test-planner

agent creates a structured implementation plan:

Groups files into logical phases (2-5 phases typical)

Prioritizes by complexity and dependencies

Specifies test cases for each file

Defines success criteria per phase

Output:

.testagent/plan.md

Step 5: Implementation Phase (Automatic)

The

polyglot-test-implementer

agent executes each phase sequentially:

Read

source files to understand the API

Write

test files following project patterns

Build

using the

polyglot-test-builder

subagent to verify compilation

Test

using the

polyglot-test-tester

subagent to verify tests pass

Fix

using the

polyglot-test-fixer

subagent if errors occur

Lint

using the

polyglot-test-linter

subagent for code formatting

Each phase completes before the next begins, ensuring incremental progress.

Coverage Types

Happy path

Valid inputs produce expected outputs

Edge cases

Empty values, boundaries, special characters

Error cases

Invalid inputs, null handling, exceptions State Management All pipeline state is stored in .testagent/ folder: File Purpose .testagent/research.md Codebase analysis results .testagent/plan.md Phased implementation plan .testagent/status.md Progress tracking (optional) Examples Example 1: Full Project Testing Generate unit tests for my Calculator project at C:\src\Calculator Example 2: Specific File Testing Generate unit tests for src/services/UserService.ts Example 3: Targeted Coverage Add tests for the authentication module with focus on edge cases Agent Reference Agent Purpose Tools polyglot-test-generator Coordinates pipeline runCommands, codebase, editFiles, search, runSubagent polyglot-test-researcher Analyzes codebase runCommands, codebase, editFiles, search, fetch, runSubagent polyglot-test-planner Creates test plan codebase, editFiles, search, runSubagent polyglot-test-implementer Writes test files runCommands, codebase, editFiles, search, runSubagent polyglot-test-builder Compiles code runCommands, codebase, search polyglot-test-tester Runs tests runCommands, codebase, search polyglot-test-fixer Fixes errors runCommands, codebase, editFiles, search polyglot-test-linter Formats code runCommands, codebase, search Requirements Project must have a build/test system configured Testing framework should be installed (or installable) VS Code with GitHub Copilot extension Troubleshooting Tests don't compile The polyglot-test-fixer agent will attempt to resolve compilation errors. Check .testagent/plan.md for the expected test structure. Tests fail Review the test output and adjust test expectations. Some tests may require mocking dependencies. Wrong testing framework detected Specify your preferred framework in the initial request: "Generate Jest tests for..."