# Show HN: A free MCP server for facts LLMs get wrong (time zones, holidays, FX) > Source: > Published: 2026-10-19 00:20:09+00:00 Give AI agents like Claude, ChatGPT and Cursor exact, deterministic tools through the Model Context Protocol No sign-up needed · 50 free calls a day 16 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. https://apistack.online/api/mcp/facts ``` claude mcp add --transport http apistack-facts https://apistack.online/api/mcp/facts ``` `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 Full catalog · API key Add 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. `?categories=finance,utilities` or `?apis=email-address-validator` to the URL https://apistack.online/api/mcp/connect Replace YOUR_API_KEY with the key from your [dashboard](https://apistack.online/dashboard) (free account works). ``` claude mcp add --transport http apistack https://apistack.online/api/mcp/connect \ --header "x-api-key: YOUR_API_KEY" ``` Watch the 90-second setup · 1:34 Connect APIStack to Claude Code, Cursor, VS Code or your own agent, with a real agent run. Single-purpose servers with hand-written tools (Pro and Enterprise). Dedicated servers require a PRO or Enterprise subscription (the unified endpoint above works on every plan).[Sign in](https://apistack.online/sign-in) to access. AI-ready Model Context Protocol (MCP) servers that integrate with your AI tools. Bridge your applications and AI assistants with contextual, data-aware conversations. Our 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. Stay tuned for updates on our progress!