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

Exposes free-tier AI APIs as MCP tools for AI agents, enabling text generation, web search, embeddings, and vision analysis with automatic failover and capability routing.

Provides Dify apps with a secure, app-scoped MCP tool catalog and action gateway for authorized FlowFlox operations, enabling intent-driven planning and fixed operational processes without exposing global credentials.

A dedicated server for Oracle Cloud Infrastructure (OCI) Core Services that enables management of compute instances and network operations with LLM-friendly structured responses.

An MCP server that exposes 43 domain tools behind 4 meta-tools, applying guardrails such as budgets, rate limits, schema validation, human-in-the-loop confirmation for mutations, PII redaction, and an append-only audit log while reducing context window usage.

Enables AI agents to access DDG's payable services including checkout/payment conformance, MCP/tool security audits, agent-discovery repair, and buyer-agent smoke probes, with structured payment challenges.

MCP Server for Google Cloud Healthcare API enables Agentic AI for a variety of FHIR-based digital health solutions, from smarter clinical workflows for Health Systems to Pre-Auth frameworks for Payers!

An MCP server providing risk-aware API governance tools for AI agents. Agents call preflight checks before tool calls or merges to verify API contracts are safe. Returns risk score, blast radius, agent impact, economic cost, and a deterministic ALLOW/WARN/REQUIRE_APPROVAL/BLOCK decision. MCP endpoint: https://app.coderifts.com/mcp

An MCP server that exposes any REST API to LLMs through runtime discovery, providing tools to browse endpoints, fetch schemas, and apply business rules without hardcoding or schema duplication.

Persistence, headed Chromium browser control for MCP clients like OpenCode and Claude Code, enabling navigation, inspection, clicking, filling, and human-gated actions on JavaScript-heavy or login-walled pages.

A passive MCP server that exposes a toolbox of executable tools (shell, network, HTTP, AI search, SSH, S3 file operations) to autonomous agents via Streamable HTTP, with strong security features including Docker sandboxing and WAF.

Enables MCP-compatible agents to discover and call x402 paid services from a directory of over 2,000 APIs.

Transforms any API into an intelligent MCP agent in seconds, enabling natural language interaction with APIs through the Model Context Protocol.

Enables deployment of a remote Model Context Protocol server on Cloudflare Workers without authentication. Allows custom tool definitions and connection from MCP clients like Claude Desktop or Cloudflare AI Playground.

Provides pre-fetch routing intelligence for AI agents by recommending the cheapest reliable route (HTTP, browser, machine endpoint, or avoid) before visiting a URL.

An MCP (Model Context Protocol) server implementation using HTTP SSE (Server-Sent Events) connections with built-in utility tools including echo, time, calculator, and weather query functionality.

A Python-based MCP server that provides coordinate conversion between latitude/longitude and UTM/TWD97, along with various civil engineering calculation tools for LLM and AI application integration.

Structured web extraction for AI agents. Pass any URL and a prompt, get clean JSON data back. Native MCP server with 100 free requests/month.

Enables web ChatGPT to drive durable, sandboxed Claude Code sessions on a local Mac, with controlled read, modify, verify, and recover operations via six session control tools.

A production-grade MCP server that provides a centralized microservice toolkit for LLM agents, enabling web search and extensible tool integration.

Provides full Devin API coverage via MCP servers, enabling programmatic management of sessions, knowledge, playbooks, secrets, schedules, and attachments, plus a documentation-only DeepWiki proxy.