US sales/use tax, nexus thresholds, capital gains and 1099-DA tools for AI agent transactions.
Tax compliance for MCP tool developers and AI agents, powered by AgentTax.
If you build MCP tools that charge for usage, you have sales tax obligations in states where your buyers are located. Most payment processors don't handle this correctly for digital services.
Add AgentTax to your MCP setup and call track_payment after every payment. That's it.
{
"mcpServers": {
"agenttax": {
"command": "npx",
"args": ["@agenttax/mcp-server"],
"env": {
"AGENTTAX_API_KEY": "atx_live_your_key"
}
}
}
}
After a payment:
track_payment({
amount: 49.00,
buyer_state: "TX",
buyer_zip: "78701",
description: "MCP API access — monthly subscription",
payment_id: "pi_stripe_abc123",
source: "stripe"
})
Returns your tax liability, compliance status, and logs it to your account. All transactions are viewable in your AgentTax dashboard.
For fully automatic tax tracking without calling any tool manually, point your Stripe webhook to AgentTax:
https://agenttax.io/api/v1/webhooks/stripe?key=atx_live_YOUR_KEY
payment_intent.succeeded, checkout.session.completed, invoice.paid, charge.succeededmetadata.work_type on your Stripe products (compute | research | content | consulting | trading) for precise tax classificationEvery payment is automatically classified, taxed, and logged. No code changes required.
Requires a billing address on the Stripe payment. Enable full address collection in your Stripe Checkout settings.
claude mcp add agenttax -- npx @agenttax/mcp-server
export AGENTTAX_API_KEY=atx_live_your_key
Add to your MCP config file:
{
"mcpServers": {
"agenttax": {
"command": "npx",
"args": ["@agenttax/mcp-server"],
"env": {
"AGENTTAX_API_KEY": "atx_live_your_key"
}
}
}
}
Demo mode works without a key (50 calls/day, no account required). Tools marked "Yes" below need AGENTTAX_API_KEY.
| Tool | What it does | Key needed |
|---|---|---|
track_payment | Log a payment you received and get your sales tax liability. The main tool for paid MCP servers and APIs. | Demo works; key for history |
calculate_tax | Full sales/use tax calculation with jurisdiction breakdown, audit trail, confidence score and advisories | Demo works; key for full response |
ingest_transactions | Bulk-log up to 100 transactions (e.g. x402 purchases), idempotent on external_tx_id | Yes |
list_transactions | Your transaction history with running totals | Yes |
get_nexus_thresholds | Each state's economic nexus thresholds (revenue / transaction count), notes and DOR source | No |
get_nexus | The states you have configured nexus in | Yes |
configure_nexus | Set the states you have nexus in (merge semantics) | Yes |
log_trade | Log a buy/sell; sells return realized gain/loss with cost basis | Yes |
list_trades | Trades you have logged | Yes |
export_1099_da | Draft Form 1099-DA payload for realized digital-asset gains | Yes (Pro) |
get_rates | State sales tax rates and digital-goods taxability, all 51 jurisdictions or one | No |
get_local_rate | Combined state + local rate for a zip code | No |
get_capital_gains_rates | State short/long-term capital gains rates | No |
get_pricing | Machine-readable pricing contract | No |
check_health | API health and endpoint list | No |
Read-only tools carry the MCP readOnlyHint annotation so clients can auto-approve them.
track_payment({
amount: 49.00,
buyer_state: "TX",
buyer_zip: "78701",
description: "MCP tool subscription",
payment_id: "pi_stripe_abc123",
source: "stripe"
})
Returns tax_owed, tax_rate, taxable, transaction_id and a compliance_note. Classification comes from description. Sellers get $0 in states where no nexus is configured; the response says so in nexus_warning.
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
})
Optional fields: seller_state / seller_zip (origin-sourced intrastate sales in TX, UT, AZ, TN and some OH sales), use_context (Maryland B2B), digital_content_type (with transaction_type: "digital_good"), seller_remitting.
get_nexus_thresholds({ state: "NY" }) // what triggers registration
configure_nexus({ nexus: { TX: { hasNexus: true, reason: "Economic nexus" } } })
get_nexus() // what you have configured
log_trade({ asset_symbol: "ETH", trade_type: "buy", quantity: 2, price_per_unit: 2500, asset_class: "crypto" })
log_trade({ asset_symbol: "ETH", trade_type: "sell", quantity: 1, price_per_unit: 3100, asset_class: "crypto" })
export_1099_da({ year: 2026 }) // draft, not a filed return
curl -X POST https://agenttax.io/api/v1/auth/signup \
-H "Content-Type: application/json" \
-d '{"email": "you@example.com", "password": "securepass", "agent_name": "my-mcp-server", "agent_work_type": "compute"}'
All four fields are required; agent_work_type is one of compute, research, information_service, content, consulting, trading. Save the api_key.key from the response — it's only shown once.
| Tier | Price | Calls/month |
|---|---|---|
| Free | $0 | 1,500 |
| Starter | $25/mo | 10,000 |
| Growth | $99/mo | 100,000 |
| Pro | $199/mo | 1,000,000 |
| x402 | $0.005/call in USDC on Base | Pay per call, no signup |
Current machine-readable pricing: get_pricing or GET https://agenttax.io/api/v1/pricing.
MIT
Source-derived launch command. Check the maintainer’s required arguments and credentials before running:
npx -y @agenttax/mcp-serverMerge this template into ~/Library/Application Support/Claude/claude_desktop_config.json. Keep existing servers. Add any arguments, credentials, and permissions required by the maintainer; this template has not been install-tested.
{
"mcpServers": {
"io-github-agenttax-agenttax-mcp": {
"command": "npx",
"args": [
"-y",
"@agenttax/mcp-server"
]
}
}
}Restart Claude Desktop completely for changes to take effect. Confirm the server appears connected in the client’s tool list, then try a read-only example from its documentation.
Claude Desktop setup reference@agenttax/mcp-servernpmAgentTax works with any MCP-compatible client. Copy the config snippet from the Configuration section above and add it to the file shown for your client, then restart the application.
~/Library/Application Support/Claude/claude_desktop_config.jsonRestart Claude Desktop completely for changes to take effect.~/.cursor/mcp.jsonRestart Cursor for changes to take effect..vscode/mcp.jsonReload VS Code window for changes to take effect.~/.codeium/windsurf/mcp_config.jsonRestart Windsurf for changes to take effect..mcp.jsonSave at the project root, then start Claude Code in that project and review the MCP server approval prompt. Keep real credentials out of shared files.