0s and 1s CIS calculators — Claude Code MCP server: setup guide
Remote MCP server calculating UK Construction Industry Scheme deductions, filing cutoffs, and late penalties. Connects over HTTP without an API key.
claude mcp add --transport http cis https://0sand1s.co.uk/mcpWhat 0s and 1s CIS calculators does
This server equips an assistant with calculation routines for the UK Construction Industry Scheme. It determines tax deductions on subcontractor invoices net of materials and VAT. It also handles reverse calculations to gross up an agreed net figure, checks turnover criteria for gross payment eligibility, and confirms whether HMRC verification is pending before cash goes out.
All tools run via remote HTTP at https://0sand1s.co.uk/mcp. The service keeps no query logs and requires zero credentials. The endpoint throttles traffic at 60 requests per minute per IP, which limits continuous bulk calculations across large accounting databases. Dates must follow YYYY-MM-DD.
What it helps with
- calculate CIS deductions split between labour, VAT, and materials
- find monthly filing cutoffs and electronic payment due dates
- evaluate tiered penalties for overdue CIS300 returns
- check contractor turnover against gross payment rules
Example prompts for the agent
- Calculate the CIS deduction for a 1200 pound invoice with 300 pounds in materials at 20% rate.
- Find the filing deadline and electronic payment date for 2025-05-10.
- Check whether this subcontractor must be verified with HMRC before payment.
How to install 0s and 1s CIS calculators
Platform CLI: remote server
claude mcp add --transport http cis https://0sand1s.co.uk/mcpPlatform CLI: remote server
codex mcp add 0s-and-1s-cis-calculators --url https://0sand1s.co.uk/mcpConfig file
{
"mcpServers": {
"0s-and-1s-cis-calculators": {
"url": "https://0sand1s.co.uk/mcp"
}
}
}Config file
{
"servers": {
"0s-and-1s-cis-calculators": {
"type": "http",
"url": "https://0sand1s.co.uk/mcp"
}
}
}Platform CLI: remote server
gemini mcp add -t http 0s-and-1s-cis-calculators https://0sand1s.co.uk/mcpStep by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about 0s and 1s CIS calculators
How to install 0s and 1s CIS calculators in Claude Code?
Run claude mcp add --transport http cis https://0sand1s.co.uk/mcp in your terminal.
What does 0s and 1s CIS calculators do?
It runs computations under UK Construction Industry Scheme rules, including tax deductions, nil return checks, turnover thresholds, and filing penalty tracking.
Does this MCP server require an account?
No credentials or sign-ups are needed, though requests are capped at 60 calls per minute from a single IP address.
