"Free tools or resources that do not require an API" matching MCP servers:

A comprehensive suite of HTTP and API testing tools that enables AI agents to perform requests, check endpoint health, and decode JWTs. It also provides utilities for URL parsing and detailed security analysis of HTTP response headers.

Code Mode MCP server for the OVH API. Two tools (search + execute) give LLMs access to all OVH endpoints via sandboxed JavaScript.

Webhook management and testing tools for AI agents. Provides tools for sending, validating, generating, and debugging webhooks.

An MCP server that enables LLMs to make arbitrary HTTP requests (GET, POST, PUT, DELETE, etc.) with custom headers, bodies, and cookies, supporting JSON and error handling.

An MCP server that makes backend API requests and packages request+response pairs as evidence to prove an endpoint works.

A Swagger/OpenAPI query tool for MCP clients like Cursor, enabling AI assistants to browse, search, and retrieve detailed API type information.

A Model Context Protocol server that creates tools from API configurations defined in YAML files, allowing easy integration of external APIs into an MCP ecosystem without coding.

Enables interaction with Nullplatform's API endpoints for managing deployments, scopes, services, and other cloud resources through natural language using the official OpenAPI specification.

Enables agents to invoke any REST or SOAP service by sending a normalized payload, with support for API key, Basic, Bearer, and OAuth2 auth. Connectors can be registered once and reused by name.

An MCP server that crawls API documentation websites and exposes their content to AI models, enabling them to search, browse, and reference API specifications.

Exposes REST API endpoints defined in an OpenAPI Specification as MCP tools, allowing AI models to call them via the ModelContext Protocol.

Turns an OpenAPI specification into a broker-published slot of curated, LLM-ready tools that a human operator reviews, tests, and approves before anything goes live. The resulting tools are declarative and run under the broker's authorization, audit, execution limits, and secret handling.

Provides a standardized MCP interface for interacting with HTTP tools and services, enabling unified API access and management.

Enables AI assistants like Claude to interact with any REST API through typed, validated MCP tools. Provides a pattern to wrap REST APIs as MCP servers.

Enables natural-language chat-driven API testing, letting users upload API specs, run deterministic pytest checks against live targets, inspect results, create defects, and view failure trends.

Enables LLMs to make arbitrary HTTP API requests with any method and full control over headers, query parameters, and body.

Enables read-only exploration of YApi projects, categories, and interface docs, and deterministic TypeScript/JavaScript API request function and type generation through a preview-then-apply workflow.

Starter scaffold for a workshop to build an MCP API testing server, intended to be extended through incremental steps.

A full-stack API automation testing server that parses OpenAPI/Swagger/Postman/HAR specs, generates comprehensive test scenarios and executable code, and provides AI-powered review and auto-fix.

Enables interaction with Users and Products through a CRUD service REST API, providing tools for listing, creating, reading, updating, and deleting records via HTTP transport.