AgentTax MCP Server

Tax compliance tools for AI agents, powered by AgentTax.

This MCP server gives any AI agent (Claude, Cursor, Windsurf, etc.) native access to sales tax calculation, capital gains tracking, and tax rate data — no HTTP code required.

Install

Claude Code

claude mcp add agenttax -- npx @agenttax/mcp-server

Then set your API key:

export AGENTTAX_API_KEY=atx_live_your_key

Or use demo mode (no key, 50 calls/day).

Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "agenttax": {
      "command": "npx",
      "args": ["@agenttax/mcp-server"],
      "env": {
        "AGENTTAX_API_KEY": "atx_live_your_key"
      }
    }
  }
}

Tools

calculate_tax

Calculate US sales/use tax for an AI agent transaction.

calculate_tax({
  role: "buyer",
  amount: 500,
  buyer_state: "TX",
  buyer_zip: "78701",
  transaction_type: "compute",
  work_type: "compute",
  counterparty_id: "seller-agent-123",
  is_b2b: true
})

Returns tax amount, rate, jurisdiction breakdown, audit trail, and advisories.

log_trade

Log a buy or sell for capital gains tracking.

log_trade({
  asset_symbol: "COMPUTE",
  trade_type: "buy",
  quantity: 100,
  price_per_unit: 12.50
})

Sell trades return realized gain/loss with cost basis (FIFO, LIFO, or Specific ID).

get_rates

Get tax rates for all 51 US jurisdictions or a single state.

get_rates({ state: "TX", explain: true })

configure_nexus

Set which states you have economic nexus in. Required for sellers to get non-zero tax results.

configure_nexus({
  nexus: {
    TX: { hasNexus: true, reason: "Economic nexus" },
    NY: { hasNexus: true, reason: "Physical presence" }
  }
})

check_health

Check API health and available endpoints.

check_health()

Get an API Key

curl -X POST https://agenttax.io/api/v1/auth/signup \
  -H "Content-Type: application/json" \
  -d '{"email": "[email protected]", "password": "securepass", "agent_name": "my-agent"}'

Save the api_key.key from the response — it's only shown once.

Pricing

Tier	Price	Calculations
Free	$0	100/month
Starter	$25/mo	10,000/month
Growth	$99/mo	100,000/month
Pro	$199/mo	1,000,000/month
x402	~$0.001/call	Unlimited

Links

• AgentTax
• API Docs
• Agent Integration Guide
• GitHub

License

MIT