PictMCP

Pairwise Testing for the AI

PictMCP is an MCP (Model Context Protocol) server that provides pairwise combinatorial testing capabilities to AI assistants.

Why use this?

• LLMs struggle with strict algorithmic data processing - Combinatorial test generation requires precise mathematical algorithms that LLMs cannot reliably execute
• Offload complex logic - This tool manages the combinatorial logic that is difficult for LLMs, allowing them to focus on test design and interpretation

Prefer a GUI? Check out PictRider.

Features

• 🔒 Local Processing - All processing runs locally with no external network calls
• ⚡ WebAssembly Powered - Fast execution using the PICT algorithm compiled to WebAssembly
• 🔗 Constraint Support - Define constraints to filter out invalid parameter combinations
• 📊 Structured Output - Returns well-structured JSON results for easy integration

Installation

Prerequisites

• Node.js (v24 or higher)

MCP Client Configuration

Add the following configuration to your MCP client. This is an example configuration; the exact format may vary depending on your client. Please refer to your MCP client's documentation for details.

{
  "mcpServers": {
    "PictMCP": {
      "command": "npx",
      "args": ["pictmcp"]
    }
  }
}

Quick Start

Once installed, you can ask your AI assistant to generate test cases using pairwise combinatorial testing.

Example Prompt

Generate test cases for a login form with the following parameters:

• Browser: Chrome, Firefox, Safari
• OS: Windows, macOS, Linux
• Language: English, Japanese, Spanish

The AI assistant will use the generate-test-cases tool to create an optimized set of test cases that covers all pairwise combinations.

Example with Constraints

Generate test cases for:

• Browser: Chrome, Firefox, Safari, Edge
• OS: Windows, macOS, Linux
• With constraint: Safari only works on macOS

The tool supports PICT constraint syntax to exclude invalid combinations.

FAQ

Does this communicate with external servers?

No. All processing runs locally with no external network calls.

I already use the pict CLI. Do I need this?

If your AI agent can execute CLI commands directly, you may not need this tool. However, PictMCP provides:

• A standardized MCP interface for AI assistants
• No need to install PICT separately (WebAssembly-based)
• Structured JSON output instead of TSV

What is pairwise testing?

Pairwise testing (also known as all-pairs testing) is a combinatorial testing method that generates test cases covering all possible pairs of input parameters. This significantly reduces the number of test cases while maintaining high defect detection rates.

What constraint syntax is supported?

PictMCP supports the full PICT constraint syntax. See the PICT documentation for details.

License

This project is licensed under the MIT License—see the LICENSE file for details.