API Tester MCP Server

API Tester MCP Server

Vikrant-Khedkar

Makes HTTP requests and tests APIs on your behalf without exposing your API keys in chat conversations. Includes specific support for OpenAI API testing.

A Model Context Protocol server that allows Claude to make API requests on your behalf, providing tools for testing various APIs including HTTP requests and OpenAI integrations without sharing your API keys in the chat.

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What it does

  • Send HTTP requests with custom headers and payloads
  • Test REST APIs with GET, POST, PUT, DELETE methods
  • Make OpenAI API calls without exposing keys
  • Debug API responses and status codes
  • Test authentication flows securely

Best for

API developers testing endpoints during developmentDebugging third-party API integrationsSecurely testing OpenAI API calls
Keeps API keys private and secureBuilt-in OpenAI API support

About API Tester MCP Server

API Tester MCP Server is a community-built MCP server published by Vikrant-Khedkar that provides AI assistants with tools and capabilities via the Model Context Protocol. API Tester MCP Server — secure API testing and API sandbox for AI that lets Claude make HTTP requests and act as an Open It is categorized under developer tools.

How to install

You can install API Tester MCP Server in your AI client of choice. Use the install panel on this page to get one-click setup for Cursor, Claude Desktop, VS Code, and other MCP-compatible clients. This server runs locally on your machine via the stdio transport.

License

API Tester MCP Server is released under the MIT license. This is a permissive open-source license, meaning you can freely use, modify, and distribute the software.

API Tester MCP Server

This is a Model Context Protocol (MCP) server that allows Claude to make API requests on your behalf. It provides tools for testing various APIs, including a dedicated integration with OpenAI's APIs.

Features

  • Make HTTP requests (GET, POST, PUT, DELETE) to any API
  • Test OpenAI's GPT models without sharing your API key in the chat
  • Generate images with DALL-E
  • Properly formatted responses for easy reading

Setup

Prerequisites

  • Python 3.10 or higher
  • MCP SDK 1.2.0 or higher

Installation

  1. Install the required dependencies:
pip install "mcp[cli]" httpx python-dotenv
  1. Set your OpenAI API key using one of these methods:

Option 1: Environment Variables

# On Windows (PowerShell)
$env:OPENAI_API_KEY = "your-api-key"

# On Windows (Command Prompt)
set OPENAI_API_KEY=your-api-key

# On macOS/Linux
export OPENAI_API_KEY="your-api-key"

Option 2: Using a .env File (Recommended)

Create a .env file in the project directory (copy from .env.example):

OPENAI_API_KEY=your_openai_api_key_here

Running the Server

python main.py

Using with Claude

Once your server is running, you can connect it to Claude for Desktop by configuring it in the Claude Desktop config file.

Example Prompts

General API Testing

Use the get_request tool to fetch data from https://jsonplaceholder.typicode.com/posts/1
Use the post_request tool to send data to https://jsonplaceholder.typicode.com/posts with this JSON body: {"title": "Test Post", "body": "This is a test", "userId": 1}

Using OpenAI Tools

Use the openai_chat_completion tool with:
prompt: "Write a short poem about artificial intelligence"
system_message: "You are a helpful assistant that writes creative poetry"
model: "gpt-4"
Use the openai_image_generation tool with:
prompt: "A futuristic city with flying cars and tall glass buildings at sunset"
size: "1024x1024"

Available Tools

General API Tools

  • get_request: Make GET requests to any URL
  • post_request: Make POST requests with JSON bodies
  • put_request: Make PUT requests with JSON bodies
  • delete_request: Make DELETE requests

OpenAI-Specific Tools

  • openai_chat_completion: Generate text using OpenAI's chat models
  • openai_image_generation: Generate images using DALL-E

Security Notes

  • Your OpenAI API key is stored in the server and not exposed in the chat
  • API usage will count against your OpenAI quota and may incur charges
  • For production use, always set the API key as an environment variable or use a .env file
  • The .env file is included in .gitignore to prevent accidentally committing your API key

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