"Understanding Prompts or Prompt Engineering" matching MCP connectors:

Open AI Visibility Index for crypto and Web3. Weekly share-of-answer measurements for 24 tracked brands across ChatGPT, Perplexity and Gemini, from a frozen versioned prompt panel. Five read-only tools: full index, per-brand lookup, brand list, complete measurement history and methodology. No auth, no API key. Data is CC BY 4.0 with a permanent archive of every weekly snapshot, so any figure can be verified independently.

Open AI Visibility Index for SaaS and AI tools. Weekly share-of-answer measurements for 20 tracked brands across ChatGPT, Perplexity and Gemini, from a frozen versioned prompt panel. Five read-only tools: full index, per-brand lookup, brand list, complete measurement history and methodology. No auth, no API key. Data is CC BY 4.0 with a permanent archive of every weekly snapshot, so any figure can be verified independently.

Anonymous read-only Formula 1 tools, resources, prompts, completion, and interactive dashboard.

Query FDA data on drugs, food, devices, and recalls via openFDA. STDIO or Streamable HTTP.

Is this product recalled in the EU? 46,506 official Safety Gate alerts by GTIN, brand or name.

Public holidays for 100+ countries — by year, or the next ones coming up. Via Nager.Date.

A machine-readable directory where AI products register themselves so AI agents can discover them. Ask it in natural language (NLWeb), call it as an MCP server over HTTP, or search the JSON API. Autonomous registration via GitHub issues, free listings, per-listing pages with schema.org JSON-LD.

Weather, climate, terrain, fire and flood risk data for any point or polygon on Earth. Free tier.

SEC EDGAR fundamentals as agent tools: look up or screen US public companies. Free, no key, CC0.

Semantic search across Japan's government white papers, in English or Japanese. Free beta.

Citation-health over a CC0 citation graph: what supports, refutes, or cites a paper. Read-only.

Structured data on wheelchair-accessible & public toilets across Japan for AI agents and travel/accessibility apps. 526 Tokyo stations (each mapped to its nearest station exit) + 612 municipalities. Station names accept Japanese or romaji. Free tier with API key.

Query US tap-water quality from the EPA's SDWIS records — by city, system, or contaminant.

Free — no API key required. Enrich by domain or name. Country, contacts, social profiles.

It connects with Smart Data models database with more than 1000 open licensed data models and helps you to create applications and systems interoperable with existing standards or real applications

250+ finance tools from Financial Modeling Prep, Alpha Vantage, AkShare, Polymarket, and Dome. Stock data, forex, financial statements, prediction markets, DCF valuations. Starts at $0.01/call. Get your API key at app.xpay.sh or xpay.tools

Search EU TED procurement notices by CPV, country, keyword, value, or type.

Fact-check claims against independent sources — fast verdict or deep multi-step investigation.

Find recent or archived satellite imagery for any place on Earth by location and date.

Scrape arXiv, OpenAlex and Crossref papers by author, topic, journal or DOI. Pay per row.