Endpoint
https://randomanvil.com/mcp — MCP Streamable HTTP transport (JSON-RPC 2.0 over POST), no authentication, read-only tools. Protocol versions 2025-06-18, 2025-03-26 and 2024-11-05 are accepted.
Tools
| Tool | What it does |
|---|---|
add_business_days | Date that is N business days after or before a start date (Excel WORKDAY semantics; start date not counted). Returns the date, weekday, calendar-day span and every weekend day and holiday it skipped. |
count_business_days | Working days between two dates with a breakdown: calendar days = working days + weekend days + holidays (NETWORKDAYS semantics; both ends included by default). |
working_days_until | Working days remaining from a given "today" until a target date — the countdown version. |
list_public_holidays | National public holidays for a country and year, with observed and substitute dates. |
All tools take country (US, GB, CA, AU, DE or NONE), a weekend list (default Saturday and Sunday; use ["sunday"] for a six-day week) and custom_holidays for company or regional days off. Dates are ISO YYYY-MM-DD. Results carry both a human-readable sentence and structured JSON.
Connect it
ChatGPT
Settings → Apps & Connectors → Advanced settings → turn on Developer mode → Create → name it "Random Anvil", paste https://randomanvil.com/mcp, authentication None. Then start a chat, enable the connector from the tools menu and ask a business-day question.
Claude
Settings → Connectors → Add custom connector → name "Random Anvil", URL https://randomanvil.com/mcp, no OAuth. In Claude Code: claude mcp add --transport http randomanvil https://randomanvil.com/mcp.
Cursor, Windsurf, VS Code and others
Any client that supports remote (HTTP) MCP servers works; add a server with the URL above and no headers. A minimal config entry looks like {"randomanvil": {"url": "https://randomanvil.com/mcp"}}.
Try these prompts
- "What date is 15 business days after 2026-11-16 in the US?"
- "How many working days are there in Q4 2026 for a UK company?"
- "How many working days until 2026-12-31 if today is 2026-09-15, excluding German public holidays?"
- "List Canada's federal holidays for 2027."
Notes
Holiday rules cover national or federal holidays only (rules version 2026-09); state and regional days are not included — pass them as custom_holidays. The server keeps a minimal usage log (tool name, parameter shape, timing, client name) to see which tools are useful; it does not store the dates you ask about. See the privacy page. Questions or a client that does not connect: [email protected].
Frequently asked questions
Is there an API key or a cost?
No. The server is free and unauthenticated; tools are read-only.
Does the assistant know what "today" is?
The tools take explicit dates, so the assistant resolves "today" in your timezone and passes it in. This avoids the server guessing your timezone.
Which countries are supported?
United States, United Kingdom (England & Wales), Canada, Australia and Germany at the national level, plus custom dates for anything else.
Can I self-host it?
The server is a single dependency-free Node.js file that reuses the same engine as this site. Contact us if you want the source.