"Examples of MCPs (Microservices Communication Protocols) That Do Not Require API Keys" matching MCP connectors:
GET /v1/connectors – MCP directory API referenceMatching Connector Tools:
Shared project memory for AI coding agents: decisions, lessons, risks and tasks in one graph.
Validate and generate German e-invoices (XRechnung, ZUGFeRD) against the official KoSIT rules. Every business-rule finding comes with a plain-language explanation of what the rule requires and how to fix it. Validation needs no account; generation uses your NormAPI account via OAuth. Invoices are never stored.
Writes your daily standup from GitLab or GitHub merge request state: what's ready, blocked or waiting on your review, and why a pipeline is red, read from the failing job log. OAuth sign-in, no API keys; can post the note to Slack, Discord or Google Chat on a schedule.
Generate synthetic random user data for testing, demos, and development without using real persona.
npm package trends and weekly downloads over time. Free key at trendsmcp.ai
Open AI models through one OpenAI-compatible API: chat, live model list, prices and cost estimates.
Signed, traced record of what an npm package or file attempts when run, network included. No key.
Agent-native registry to discover APIs, MCP servers and CLIs, with live health checks.
Run Python, Java, C, C++, C#, Go, Rust and 39 more languages, each run in a fresh, offline sandbox.
Onchain DeFi intelligence API for Base, payable per call with x402 (USDC). Live MCP tools: get_bot_status (Telegram bot health), get_market_stats (market snapshot), get_onchain_sales (proven revenue from live x402 routes). Built for agents that need verifiable onchain data — whale flow, signals, and sales evidence at $0.003/call.
Design quality gate for AI-generated UI: score any URL on 45 deterministic checks, A–F grade.
A portable knowledge-graph memory you pass in and get back. No database. 4 of 6 free.
Prove end users to agents and apps: login-links, OIDC clients, and API keys over remote MCP
Thermal label MCP server: render, validate, debug and convert ZPL, EPL, TSPL and CPCL labels.
Publishes what an AI made — a page, a markdown or PDF doc, or a whole site — to a live HTTPS link. Runs locally over stdio from the @drop2run/mcp npm package, or hosted at https://mcp.dropto.run/mcp for chats that connect by URL.
Kaiva Bridge turns your API, database or documents into a managed MCP server for Claude, ChatGPT, Cursor and VS Code. Point it at an OpenAPI or Swagger spec, an API docs link, a cURL command, a Postman collection, a GraphQL endpoint, Postgres, MySQL, MariaDB or SQL Server, spreadsheets, PDFs and other documents, or an MCP server you already run. Bridge reads the source and proposes tools, and you choose which ones your AI client sees. No code to write and nothing to run. Connect this server and your agent does the setup for you: it lists your servers, shows one, drafts a new server from an OpenAPI spec, and refreshes a server's tools when its API changes. Free plan: 10 servers and 200,000 tool calls a month, no credit card. Pricing: https://kaiv.ai/bridge/pricing Security: https://kaiv.ai/bridge/security Docs: https://kaiv.ai/bridge/docs
Coding agents in multi-service codebases routinely rebuild existing helpers, trust stale type definitions, and modify API contracts without knowing who consumes them. Carrick solves this by indexing your entire TypeScript ecosystem across service and repository boundaries. By integrating deeply with the TypeScript compiler, Carrick traces every route, type, and cross-service call while recording function behaviour so agents search by intent rather than name. Delivered via MCP for AI agents and LSP for IDEs, Carrick ensures models see existing endpoints and utilities before generating new code. The scanner is source-available and runs from your CLI or CI pipeline.
Context for coding agents: checks a GitHub or Linear issue is ready before your agent starts it.
Check a product CSV, handles, variant matrices and metafield keys. 4 of 6 free.
Ask your assistant for an app and it lands on your phone: offline, data on the phone.
