API Reference

Tax intelligence, gain/loss tracking, and compliance for AI-to-AI transactions.

⚡ Quick Start

Get tax-compliant in under 5 minutes.

1

Create Account

POST /api/v1/signup with your email. Save the API key — shown once.

2

Calculate Tax

POST /api/v1/calculate with role, amount, buyer_state, and transaction_type.

3

Track Gains

POST /api/v1/trades to log buys/sells. Cost basis and gains are automatic.

Full example — curl

# 1. Sign up
curl -X POST https://agenttax.io/api/v1/signup \
  -H "Content-Type: application/json" \
  -d '{"email":"agent@example.com","name":"My Agent"}'

# 2. Calculate tax (seller side)
curl -X POST https://agenttax.io/api/v1/calculate \
  -H "Content-Type: application/json" \
  -H "X-API-Key: atx_live_YOUR_KEY" \
  -d '{"role":"seller","amount":2500,"buyer_state":"TX",
       "transaction_type":"api_access","counterparty_id":"buyer_01"}'

# 3. Log a trade
curl -X POST https://agenttax.io/api/v1/trades \
  -H "Content-Type: application/json" \
  -H "X-API-Key: atx_live_YOUR_KEY" \
  -d '{"asset_symbol":"COMPUTE_CREDIT","trade_type":"buy",
       "quantity":100,"price_per_unit":0.25}'

🔑 Authentication

Include your API key in every authenticated request.

Header format

X-API-Key: atx_live_YOUR_KEY_HERE

Also accepts Authorization: Bearer atx_live_... — Keys are SHA-256 hashed. Raw key shown once at creation.

Free

100/mo

Hard cutoff

Starter — $25/mo

1,000/mo

$0.05 overage

Growth — $99/mo

10,000/mo

$0.02 overage

Pro — $199/mo

40,000/mo

$0.01 overage

🧮 Tax Engine

Calculate sales tax, use tax, and 1099 obligations. Specify your role — seller gets collection obligations; buyer gets use tax exposure and seller remittance verification.

POST/api/v1/calculate🔑 API Key

Calculate tax obligations. Sellers get sales tax with nexus/exemption checks. Buyers get use tax, seller remittance status, and 1099 tracking.

POST/api/v1/calculate🔑 API Key

Buyer example — use tax, seller remittance verification, 1099 tracking.

GET/api/v1/transactions🔑 API Key

List transaction history with tax calculations.

📊 Gain/Loss Tracker

Track trades, manage cost basis lots (FIFO/LIFO/Specific ID), and calculate realized capital gains. Supports fractional quantities to 8 decimals — crypto, compute credits, data bundles, any tradeable AI agent asset.

POST/api/v1/trades🔑 API Key

Log a buy or sell. Buys create cost basis lots. Sells match lots and compute realized gains with holding period classification.

POST/api/v1/trades🔑 API Key

Sell — matches lots via FIFO and computes realized gains.

GET/api/v1/trades🔑 API Key

List trades with per-asset summary stats.

👤 Accounts & Keys

Create accounts, manage API keys, handle dashboard authentication.

POST/api/v1/signup

Create a free account instantly. No credit card.

POST/api/v1/auth/signup

Full registration with agent, org, and optional network profile.

POST/api/v1/auth/login

GET/api/v1/auth-me🔑 Session Token

Get current user profile and usage.

GET/api/v1/keys🔑 API Key

List API keys (prefixes only).

POST/api/v1/keys🔑 API Key

Generate a new API key.

DELETE/api/v1/keys🔑 API Key

Revoke a key by prefix.

POST/api/v1/checkout

Stripe checkout to upgrade plan.

🌐 Agent Network

POST/api/v1/network🔑 API Key

Create or update your network profile.

GET/api/v1/network🔑 API Key

Get your network profile.

GET/api/v1/network-directory

Browse public agents.

POST/api/v1/nexus🔑 API Key

Configure nexus status for a state.

GET/api/v1/nexus🔑 API Key

List all nexus configs.

📋 Compliance

Nexus threshold monitoring, idempotency for agent retries, and 1099-DA draft exports.

GET/api/v1/nexus-alerts🔑 API Key

Check economic nexus thresholds across all 51 US jurisdictions. Returns alerts for states where your YTD revenue is ≥80% of the threshold.

GET/api/v1/export/1099-da🔑 API Key

Generate a draft 1099-DA (Digital Asset Proceeds) export. Returns JSON matching IRS form fields — ready for tax software import or accountant handoff.

🔁 Idempotency Keys

AI agents frequently retry failed network calls. To prevent duplicate tax entries or double-counted trades, include an Idempotency-Key header on POST requests.

Usage

curl -X POST https://agenttax.io/api/v1/trades \
  -H "Content-Type: application/json" \
  -H "X-API-Key: atx_live_YOUR_KEY" \
  -H "Idempotency-Key: 550e8400-e29b-41d4-a716-446655440000" \
  -d '{"asset_symbol":"ETH","trade_type":"buy","quantity":1,"price_per_unit":3000}'

# Retry with same key → returns cached response, no duplicate entry
# Response includes: X-Idempotency-Status: cached

Supported on

POST /calculate, /trades

Key TTL

24 hours

Cache header

X-Idempotency-Status

📖 Reference Data

Public endpoints — no authentication required.

GET/api/v1/health

API status and database connectivity.

GET/api/v1/rates

Tax rates for all 50 states + DC. Filter by state.

POST/api/v1/verify

Cross-check a tax rate against AgentTax's verified sources.

GET/api/v1/blog

Blog articles with metadata (20 articles).

GET/api/v1/rss

RSS feed for blog syndication.

Questions? Beardsley@agenttax.io