"Services or tools available for free without requiring an API key" matching MCP servers:

Gateway connector between LLM agents and world data, providing access to financial market prices, macroeconomic indicators, and news through a bundled endpoint catalog.

MCP server that gives AI agents isolated, named Linux computers with stable IDs and lifecycle control. Supports multiple backends like Docker, Fly Machines, Modal, and E2B, with a dashboard for managing sandboxes.

The best free social media publishing and scheduling API. Publish to 11 platforms from a single API call. Schedule posts, upload media, track analytics, and automate your social media workflow.

Exposes structured documentation for 200+ Trimble Connect API endpoints and provides tools for AI-assisted development of Trimble Connect extensions and applications.

MCP server that resolves postal/ZIP codes to place names, states, and coordinates using Zippopotam.us. Free, no API key required.

Enables real-time domain registration lookups via RDAP, including availability, expiration, and registrar details, with no API key required. Supports natural language queries like 'is example.com available?' or 'when does example.com expire?'.

Provides live product search, offer comparison, and price history retrieval from BestPrice.gr through three read-only tools, enabling AI applications to query shopping data without an API key.

Enables currency conversion and exchange rate lookups using real ECB reference rates, free and without an API key. Supports natural language queries like 'convert 100 USD to EUR' or 'what's the exchange rate between GBP and JPY?'.

Provides real, official public holiday data for ~100 countries with tools to list holidays for a year and check if a specific date is a holiday. Free, no API key required, powered by Nager.Date.

Provides programmatic access to the FDIC BankFind Suite API, enabling users to query public data on FDIC-insured financial institutions, bank failures, and branch locations. It supports advanced filtering for financial reports, demographics, and institutional history without requiring an API key.

Provides real-time weather temperature queries for any city with an interactive UI form, using Open-Meteo API (no API key needed).

Provides real-time cryptocurrency prices, market cap, and 24h change using CoinGecko, with free access and no API key required.

Downloads your entire Search Console dataset into a local SQLite database, then gives your LLM a pre-built SQL query library for every standard SEO analysis type, with context available for your LLM to perform any SQL query to answer your questions and analyse for you.

Thin MCP wrapper around the SQD Portal API for blockchain data queries across multiple networks including EVM, Solana, Bitcoin, Substrate, and Hyperliquid. Provides 25 public tools for discovery, cross-chain queries, and chain-specific operations.

An interactive flashcard MCP App for Claude Desktop. Claude generates flashcards from your request or the conversation and renders them as an inline, gradeable flip-card review with spaced repetition.

Enables AI agents to read, reply, send images, and search LINE messages by logging in as a secondary device, without official API or browser.

Turns any idea, blog post, or article into hand-drawn Tinku illustrations that explain key concepts, with an interactive viewer in the chat.

This MCP server enables MCP Apps-compatible hosts to render an interactive React-based UI and invoke a sample tool over streamable HTTP or stdio transports.

Remote MCP server for 2ools—build, version, review, and export websites, web apps, and games from the AI chat you already use. This repository includes a credential-free stdio proxy and Dockerfile that forward introspection to the verified remote endpoint without mocking tools.

MCP server for Argo CD that provides multi-environment profiles, SSO or API key authentication, application search with cache, and REST API tools from the bundled OpenAPI catalog.