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

Provides 13 offline SEO and marketing tools to any MCP client, covering ad metric calculators, text and heading analysis, keyword density, and generators for meta tags, Open Graph, hreflang, schema markup, XML sitemaps, and robots.txt. Everything runs locally with no account, API key, or network calls.

Enables AI agents to query OpenRouter model information including prices, ELO rankings, context, and perform comparisons.

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.

MCP server that demonstrates the Resources feature by exposing static and dynamic resources, including contact data and personalized greetings, through MCP.

LLM routing proxy that cuts API costs 60-90% by auto-selecting the cheapest capable model across OpenAI, Anthropic, and Google. Provides stats, config, and model comparison tools via MCP.

Multi-sensory feedback MCP server for AI coding agents, providing audio, visual, haptic, and physical notifications with customizable characters and modes.

Scans code for exposed secrets, API keys, tokens, and credentials across 69 patterns covering cloud services, AI platforms, payment providers, authentication services, and databases.

A framework that provides search, fetch, and do primitives to enable AI agents to orchestrate complex tasks via sandboxed TypeScript code execution. It optimizes performance and security by reducing multiple sequential tool calls into a single, efficient inference round-trip.

Enables interaction with MongoDB databases through CRUD operations, aggregation, and schema discovery, with automatic field validation and ObjectId conversion.

Free and open-source MCP server for managing n8n workflows, executions, and tags via n8n's API. Enables workflow creation, activation, debugging, and deletion from any MCP client.

Enables Claude to connect to Figma without a paid plan, offering auto-connect and 100+ tools for document manipulation, design system sync, and code-to-Figma conversion.

Enables delegating bounded execution loops—such as failing test suites, large CI logs, build/diagnose/fix/rerun cycles, and routine repo exploration—to OpenCode, which inspects and iterates on the raw output internally. Returns only a compact structured result to the primary model, with inspect and fix modes and an escalation flag when a primary-model decision is required.

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.

A dual-transport MCP server enabling anonymous free web search via Parallel (default) or Exa (backup), with no API keys or DSH dependency, for Claude Code, Codex, and any MCP client.

A reference MCP server that connects any MCP client to a free cloud database, supporting 15 database engines with unified tools for querying, storing, listing tables, and annotating tables.

MCP-ORTools integrates Google's OR-Tools constraint programming solver with Large Language Models through the MCP, enabling AI models to: Submit and validate constraint models Set model parameters Solve constraint satisfaction and optimization problems Retrieve and analyze solution

MCP server that exposes tools to route natural language queries to typed IDs, describe catalog entries, and list repository verification commands for the m-dev-tools organization.

An MCP server that gives an AI assistant a set of real mechanical-engineering tools. Provides deterministic tools like material properties, beam analysis, unit conversion, and curve fitting for engineering calculations.

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.

A TypeScript-based MCP server that implements a simple notes system, providing resources for accessing notes via URIs, tools for creating notes, and prompts for generating summaries.