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 zonefind_meeting_time · Shared working hours across time zoneslist_public_holidays · Public holidayscheck_working_day · Is a date a working day?add_working_days · Add working daysdate_difference · Difference between two datesconvert_currency · Convert currencyvalidate_vat_number · Check an EU VAT numbervalidate_iban · Validate an IBANvalidate_email · Validate an email addressvalidate_phone · Validate a phone numberlookup_company · Look up a companycheck_url_safety · Check if a link looks riskygeocode_city · Find a cityscreen_sanctions · Screen a name against sanctions listseconomic_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 (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 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!