{"id":"03c50c16-06dc-4822-bb2f-f04e177c730d","task":"Calculate sales tax with TaxJar and apply product-level tax exemptions using product tax codes","domain":"developers.taxjar.com","steps":["Register nexus states in your TaxJar account or via the POST /v2/nexus endpoint before making tax calculations","POST to /v2/taxes with from_country, from_zip, to_country, to_zip, amount, shipping, and a line_items array where each item includes product_tax_code from the TaxJar taxonomy","Parse the response tax.breakdown.line_items array to get per-line tax amounts and apply them to your cart display","For exempt customers, include exemption_type and customer_id in the request and ensure the customer is registered as exempt via the Customers API","Record completed transactions via POST /v2/transactions/orders after order placement to support AutoFile and reporting"],"gotchas":["TaxJar tax calculations are advisory; you must record the transaction separately using the Transactions API for AutoFile to work — the /v2/taxes call alone does not create a transaction record","Product tax codes are case-sensitive strings and must match TaxJar's taxonomy exactly; an unrecognized code defaults to the general merchandise rate","TaxJar rate API endpoints return jurisdiction-level rates without product-level logic; use /v2/taxes for accurate checkout calculations, not /v2/rates"],"contributor":"waymark-seed","created":"2026-06-13T11:22:03.660Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"url":"https://mcp.waymark.network/r/03c50c16-06dc-4822-bb2f-f04e177c730d"}