"Services or tools that don't require a separate API key" matching MCP servers:

Full-stack utility API with 337+ tools including AI chat, web scraping, weather, finance, SEO, crypto, colors, readability, DNS, and more — all through a single MCP server. Pay-as-you-go credits, no API keys needed.

Amazon MCP server and Amazon product data API for AI agents. Lets Claude, Cursor, ChatGPT and other MCP clients search Amazon, get real-time prices, reviews, product details, sellers, deals and best seller ranks, or look up any ASIN. One API key, 100 free requests a month.

Enables deterministic calculations for AI API and subscription costs, meeting time zones, recurring schedules, and cron next-run previews, returning normalized inputs, units, assumptions, dated sources, and links to results.

Eight crypto and DeFi data tools for AI agents: prices, gas, one ParaSwap route quote, GoPlus token security and top-holder samples, DefiLlama yields, Hyperliquid/dYdX funding, and observed wallet balances. Inspect prices free; pay 0.001–0.008 USDC per call on Base through x402. No API key or subscription.

Enables validating JSON/JSONC, getting/setting values with jq-like paths, pretty-printing or minifying, validating against Ajv JSON Schema, and diffing local files or inline strings without network calls.

Enables AI assistants to query live football data, including fixtures, live scores, standings, statistics, betting odds, and full odds movement history for corner and card lines.

Real-time crypto, stock, and prediction-market data for agents — prices, indicators, funding rates, DeFi TVL, macro calendar, and an AI momentum score. Configure one Base wallet key and it just works. No signup, no dashboard, no subscription.

Enables AI agents to query multi-cloud costs, inventory, waste, and commitments across AWS, GCP, Cloudflare, and OVH through read-only MCP tools.

MCP tool server that gives any AI agent the ability to search, scrape, and analyze content across the internet.

Cross-chain cryptocurrency swaps via Chainflip. Get quotes, execute swaps, and track progress. No API key required to get started.

Enables AI assistants to read, write, and manage Google Docs, Sheets, and Drive files through structured MCP tools using service-account authentication, without requiring an OAuth consent screen.

Enables AI agents to perform common utility tasks through a streamable HTTP MCP endpoint, including JSON inspection, regex testing, cron parsing, hashing, base64 encoding/decoding, URL analysis, color conversion, text diffing, CSV parsing, JWT decode/verification, Markdown-to-HTML rendering, and UUID/token generation without API keys.

Provides a deterministic failure-decision API for MCP clients, returning one of six actions (RETRY_NOW, WAIT, REPAIR_REQUEST, VERIFY_FIRST, ESCALATE, ABORT) based on failure context to guide safe next steps.

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

Free Industry 4.0 / IIoT tools, no API key or account: lint MQTT Sparkplug B topics, check a Unified Namespace (UNS) for naming and hierarchy problems, and run an industrial AI-readiness diagnostic for manufacturing digital transformation and smart-factory projects. Works in Claude Code, Codex and any MCP client.

It gives AI agents one tool to access the Omega-API judge, which evaluates conversational turns and returns a decision and gate action (release, clarify, suppress, or none) to guide the agent's response.

Provides agents with real Linux VMs to run commands, manage files, expose ports, and track costs, all through an ephemeral sandbox service.

An MCP server for Canvas LMS that provides 15 curated tools for everyday student work and a gateway to reach every endpoint your Canvas instance exposes.

MCP server for file operations with non-UTF-8/Unicode encoding: Cyrillic, CP1251, CP1252, ISO-8859, KOI8 auto-detection

Provides read-only, governance-audited operations for OLVM and oVirt 4.5 engines, enabling inventory, health, capacity, and diagnosis queries over MCP and CLI with audit logging and budget guards.