IRS Taxpayer MCP Server

1

Add it to Claude Code

Run this in a terminal.

Run in terminal
claude mcp add irs-taxpayer -- npx -y irs-taxpayer-mcp
README.md

39 tax tools for US individual taxpayers with local-only calculations.

πŸ›οΈ irs-taxpayer-mcp

The most thorough open-source tax assistant for US individual taxpayers β€” powered by Model Context Protocol.

English | δΈ­ζ–‡ | EspaΓ±ol | ζ—₯本θͺž


⚠️ Disclaimer: This tool provides estimates for educational and informational purposes only. It does not constitute tax, legal, or financial advice. Always consult a qualified tax professional.

Legal Notice: This software is provided "as is" without warranty of any kind. The authors and contributors are not tax professionals, CPAs, enrolled agents, or attorneys. No attorney-client, CPA-client, or fiduciary relationship is created by using this software. Tax laws change frequently and vary by jurisdiction. The calculations may contain errors, omissions, or may not reflect the most recent legislative changes. You are solely responsible for your tax filing decisions. The authors disclaim all liability for any damages arising from the use of this software. See DISCLAIMER.md for full legal notice.

Why This MCP?

Tax season is stressful. You're juggling W-2s, 1099s, deductions, credits, and trying to figure out if you should itemize or take the standard deduction. You Google "SALT deduction limit 2025" and get 10 conflicting articles.

This MCP server puts a tax-aware assistant right inside your AI chat. Ask it anything about your tax situation in plain language, and get precise, up-to-date answers β€” with all calculations running locally on your machine. No data leaves your computer. No IRS login needed. No SSN required.

It knows about the One Big Beautiful Bill Act (2025), the latest bracket adjustments, SALT cap changes, and every major credit and deduction. It's like having a knowledgeable friend who happens to be a tax nerd.

πŸ”’ Privacy Architecture

Layer Design
All tax calculations 100% local execution β€” zero network calls
User data storage Stateless β€” nothing saved between calls
Authentication Zero credentials β€” no SSN, no IRS login
Remote data Only public IRS info (form descriptions, deadlines)
Telemetry None β€” no analytics, no tracking, no logging
Source code Fully open-source (MIT) β€” audit every calculation

⚑ Getting Started

Step 1: Add to your AI assistant

Add this to your MCP client configuration:

Claude Desktop (~/Library/Application Support/Claude/claude_desktop_config.json):

{
  "mcpServers": {
    "irs-taxpayer": {
      "command": "npx",
      "args": ["-y", "irs-taxpayer-mcp"]
    }
  }
}

Kiro (.kiro/settings/mcp.json):

{
  "mcpServers": {
    "irs-taxpayer": {
      "command": "npx",
      "args": ["-y", "irs-taxpayer-mcp"]
    }
  }
}

Cursor β€” same format in Cursor's MCP settings.

Step 2: Restart your AI assistant

After saving the config, restart the app. The MCP server will auto-download and connect.

Step 3: Start asking tax questions

That's it. Just chat naturally:

  • "Calculate my federal tax: $150k income, married filing jointly, 2 kids"
  • "Compare California vs Texas vs Washington for $200k income"
  • "I'm a freelancer making $80k β€” what are my quarterly estimated taxes?"
  • "What tax credits am I eligible for? AGI $60k, single, one child"
  • "Should I itemize or take the standard deduction? I pay $15k in mortgage interest and $12k in state taxes"
  • "Explain the Backdoor Roth IRA strategy"
  • "How much is the EITC for a family of 4 earning $35k?"
  • "I exercised ISOs this year β€” will I owe AMT?"
  • "Help me plan my year-end tax moves. I have a 401k and HSA."

Alternative: Docker

docker build -t irs-taxpayer-mcp .
docker run -i irs-taxpayer-mcp

Alternative: SSE Transport

npx irs-taxpayer-mcp --sse --port 3000
# Health check: http://localhost:3000/health
# SSE endpoint: http://localhost:3000/sse

πŸ› οΈ Tools (39)

Federal Tax Calculations

Tool What it does

Tools (3)

calculate_federal_taxCalculates federal income tax based on income, filing status, and dependents.
compare_state_taxesCompares tax burdens across different US states for a given income level.
estimate_quarterly_taxesEstimates quarterly estimated tax payments for freelancers and self-employed individuals.

Configuration

claude_desktop_config.json
{"mcpServers": {"irs-taxpayer": {"command": "npx", "args": ["-y", "irs-taxpayer-mcp"]}}}

Try it

β†’Calculate my federal tax: $150k income, married filing jointly, 2 kids
β†’Compare California vs Texas vs Washington for $200k income
β†’I'm a freelancer making $80k β€” what are my quarterly estimated taxes?
β†’Should I itemize or take the standard deduction? I pay $15k in mortgage interest and $12k in state taxes
β†’How much is the EITC for a family of 4 earning $35k?

Frequently Asked Questions

What are the key features of IRS Taxpayer?

39 tax tools for US individual taxpayers. Supports TY2024 and TY2025 tax calculations. 100% local execution with no data leaving the machine. Stateless design with no user data storage. Zero authentication or credential requirements.

What can I use IRS Taxpayer for?

Estimating federal tax liability for different income scenarios. Comparing state-level tax burdens before relocating. Calculating quarterly estimated tax payments for freelancers. Determining eligibility for tax credits and deductions. Evaluating the benefit of itemizing versus taking the standard deduction.

How do I install IRS Taxpayer?

Install IRS Taxpayer by running: npx -y irs-taxpayer-mcp

What MCP clients work with IRS Taxpayer?

IRS Taxpayer works with any MCP-compatible client including Claude Desktop, Claude Code, Cursor, and other editors with MCP support.

Turn this server into reusable context

Keep IRS Taxpayer docs, env vars, and workflow notes in Conare so your agent carries them across sessions.

Need the old visual installer? Open Conare IDE.
Open Conare