{"slug": "show-hn-a-free-mcp-server-for-facts-llms-get-wrong-time-zones-holidays-fx", "title": "Show HN: A free MCP server for facts LLMs get wrong (time zones, holidays, FX)", "summary": "APIStack released a free Model Context Protocol server that gives AI agents such as Claude, ChatGPT and Cursor 16 deterministic tools for facts the company says LLMs get wrong, including current time, public holidays, working days, currency conversion, EU VAT and IBAN validation, company lookups, URL safety checks and sanctions screening. The server at apistack.online/api/mcp/facts requires no sign-up and allows 50 free calls a day, with a free API key needed beyond that limit; a separate unified endpoint exposes three tools (search_apis, get_api_details, call_api) to keep context use low. Single-purpose servers with hand-written tools require a Pro or Enterprise subscription, while the unified endpoint works on every plan.", "body_md": "Give AI agents like Claude, ChatGPT and Cursor exact, deterministic tools through the Model Context Protocol\n\nNo sign-up needed · 50 free calls a day\n\n16 focused tools for questions agents should not answer from memory: the current time, holidays and working days, exchange rates, VAT and IBAN checks, company lookups, link safety, sanctions screening and more. Add the URL and it works right away; add a free API key when you need more than 50 calls a day.\n\nhttps://apistack.online/api/mcp/facts\n\n```\nclaude mcp add --transport http apistack-facts https://apistack.online/api/mcp/facts\n```\n\n`get_current_time` · Current time in a time zone`find_meeting_time` · Shared working hours across time zones`list_public_holidays` · Public holidays`check_working_day` · Is a date a working day?`add_working_days` · Add working days`date_difference` · Difference between two dates`convert_currency` · Convert currency`validate_vat_number` · Check an EU VAT number`validate_iban` · Validate an IBAN`validate_email` · Validate an email address`validate_phone` · Validate a phone number`lookup_company` · Look up a company`check_url_safety` · Check if a link looks risky`geocode_city` · Find a city`screen_sanctions` · Screen a name against sanctions lists`economic_snapshot` · Economic indicators for a country\nFull catalog · API key\n\nAdd one MCP server and your agent can search the whole catalog, read an API's details and run it: three tools (`search_apis`, `get_api_details`, `call_api`) instead of dozens, so it stays light on context.\n\n`?categories=finance,utilities` or `?apis=email-address-validator` to the URL\nhttps://apistack.online/api/mcp/connect\n\nReplace YOUR_API_KEY with the key from your [dashboard](https://apistack.online/dashboard) (free account works).\n\n```\nclaude mcp add --transport http apistack https://apistack.online/api/mcp/connect \\\n  --header \"x-api-key: YOUR_API_KEY\"\n```\n\nWatch the 90-second setup · 1:34\n\nConnect APIStack to Claude Code, Cursor, VS Code or your own agent, with a real agent run.\n\nSingle-purpose servers with hand-written tools (Pro and Enterprise).\n\nDedicated servers require a PRO or Enterprise subscription (the unified endpoint above works on every plan).[Sign in](https://apistack.online/sign-in) to access.\n\nAI-ready Model Context Protocol (MCP) servers that integrate with your AI tools. Bridge your applications and AI assistants with contextual, data-aware conversations.\n\nOur MCP servers are currently in development. We're working hard to bring you powerful, context-aware integrations that will revolutionize how you interact with AI.\n\nStay tuned for updates on our progress!", "url": "https://wpnews.pro/news/show-hn-a-free-mcp-server-for-facts-llms-get-wrong-time-zones-holidays-fx", "canonical_source": "https://apistack.online/mcp", "published_at": "2026-10-19 00:20:09+00:00", "updated_at": "2026-10-19 00:48:46.340487+00:00", "lang": "en", "topics": ["ai-agents", "agent-protocols", "ai-tools", "developer-tools"], "entities": ["APIStack", "Model Context Protocol", "Claude", "ChatGPT", "Cursor", "Claude Code", "VS Code"], "also_reported_by": [], "alternates": {"html": "https://wpnews.pro/news/show-hn-a-free-mcp-server-for-facts-llms-get-wrong-time-zones-holidays-fx", "markdown": "https://wpnews.pro/news/show-hn-a-free-mcp-server-for-facts-llms-get-wrong-time-zones-holidays-fx.md", "text": "https://wpnews.pro/news/show-hn-a-free-mcp-server-for-facts-llms-get-wrong-time-zones-holidays-fx.txt", "jsonld": "https://wpnews.pro/news/show-hn-a-free-mcp-server-for-facts-llms-get-wrong-time-zones-holidays-fx.jsonld"}}