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What do you want PostStack and TaxJar to do together?
Ask the assistant
Connect your AI client
Give your AI client this address.
https://mcp.apiant.aiAny client that takes a remote MCP server. Nothing to install. Create your free account, then sign in once in your browser.
Set it up in your client
Claude Code
Run this in the directory you want to work in.
claude mcp add --transport http -s project apiant-ai https://mcp.apiant.aiStart Claude Code there, approve the server, and sign in in the browser page it opens.
Claude Code guide (opens in a new tab)Claude, web and desktop
Open Customize, then Connectors, then Add custom connector, and paste the address. On Team and Enterprise an owner adds it first.
Setup guide (opens in a new tab)Cursor
Add the address to your MCP configuration as a server URL. Cursor signs you in in your browser.
Setup guide (opens in a new tab)Zed
Open Settings, then AI, then MCP Servers, then Add Server, then Add Remote Server.
Setup guide (opens in a new tab)Codex and the ChatGPT desktop app
Open Settings, then MCP servers, then Add server, and choose Streamable HTTP. From the terminal, Codex takes the address with its own add command and then signs you in.
Setup guide (opens in a new tab)Any other MCP client
Paste the address where the client asks for a remote MCP server URL, and name the server apiant-ai where it lets you. APIANT's skills reach the client over the same connection.
Setup guide (opens in a new tab)Example flows
What PostStack can start in TaxJar
When Contact Updated (instant) in PostStack
then Create a Customer in TaxJar
When New Contact (instant) in PostStack
then Create an Order Transaction in TaxJar
Starting points drawn from the triggers and actions in the catalog today. Describe the flow you need, at any depth, and your agent builds it and tests every scenario before it ships.
Everything your agent can do with PostStack and TaxJar
Triggers and actions 7 triggers · 51 actions
Trigger
Contact Deleted (instant)Fires when a contact is deleted (event: contact.deleted).
Trigger
Contact Updated (instant)Fires when a contact is updated (event: contact.updated).
Trigger
Email Bounced (instant)Fires when an email bounces (event: email.bounced).
Trigger
Email Delivered (instant)Fires when an email is delivered (event: email.delivered).
Trigger
New Contact (instant)Fires when a contact is created (event: contact.created).
Trigger
New Inbound EmailPolls for newly received inbound emails.
Trigger
New Sent Email (instant)Fires when an email is sent (event: email.sent).
Action
Add a broadcastCreate a new marketing broadcast.
Action
Add a contactCreate a new contact.
Action
Add a segmentCreate a new manual contact segment.
Action
Add a templateCreate a new email template.
Action
Add contacts to segmentAdd contacts to an existing segment.
Action
Add suppressionAdd an address to the suppression list.
Action
Cancel broadcastCancel an in-flight broadcast.
Action
Cancel emailCancel a scheduled or queued email before it sends.
Action
Delete a contactDelete a contact.
Action
Delete a templateDelete an email template.
Action
Get a contactFetch one contact by ID.
Action
Get a templateFetch one email template by ID.
Action
Get broadcastRetrieve one broadcast by its public id, including the HTML and text bodies that the list endpoint omits.
Action
Get emailFetch one sent or queued email by ID.
Action
Get email eventsGet the delivery event timeline for one email.
Action
Get inbound emailFetch one received inbound email by ID.
Action
Import contactsBulk-import a CSV list of contacts.
Action
List broadcastsList marketing broadcasts.
Action
List contactsList contacts in the account.
Action
List emailsList sent, queued, and scheduled emails.
Action
List inbound emailsList emails received via inbound parsing.
Action
List segmentsList contact segments.
Action
List suppressed addressesList addresses on the suppression list.
Action
List templatesList email templates.
Action
Send an emailSend a transactional email through PostStack.
Action
Send broadcastStart sending a broadcast to its recipients.
Action
Send emails in batchSend up to 100 emails in a single request.
Action
Update a contactUpdate an existing contact's fields.
Action
Update a templateUpdate an email template, creating a new version.
Action
Update emailReschedule a queued email's send time.
Action
Validate email addressCheck whether an email address is valid and deliverable.
Action
Calculate Sales Tax for an OrderWorks out the sales tax due on an order from the ship-from and ship-to addresses, the order amount and its line items.
Action
Create a CustomerCreates a customer in TaxJar with their exemption type and the regions the exemption applies to.
Action
Create an Order TransactionRecords a completed order in TaxJar so it counts towards your sales tax reporting.
Action
Create a Refund TransactionRecords a refund against an existing order in TaxJar so your sales tax reporting stays accurate.
Action
Get Two-Letter ISO Code for RegionLooks up the two-letter code for a state, province or country by name, using TaxJar's own list of regions.
Action
List CategoriesReturns TaxJar's product categories and the tax code to use for each one.
Action
List CustomersReturns the IDs of every customer in your TaxJar account.
Action
List Nexus RegionsReturns the states, provinces and countries where your TaxJar account has nexus and must collect tax.
Action
List OrdersReturns the IDs of the orders recorded in TaxJar, optionally limited to a date or date range.
Action
List RefundsReturns the IDs of the refunds recorded in TaxJar, optionally limited to a date or date range.
Action
Rates for LocationReturns the sales tax rates that apply at a location, broken down by state, county and city.
Action
Show a CustomerReturns one customer from TaxJar, including their exemption type and exempt regions.
Action
Show OrderReturns one order recorded in TaxJar, including its addresses, totals and line items.
Action
Show RefundReturns one refund recorded in TaxJar, including the order it applies to and the amounts refunded.
Action
Summarize Tax Rates for All RegionsReturns the minimum and average sales tax rate for every state, province and country TaxJar covers.
Action
Update a CustomerUpdates a customer in TaxJar. Only the fields you supply are changed.
Action
Update an Order TransactionUpdates an order already recorded in TaxJar. Only the fields you supply are changed.
Action
Update a Refund TransactionUpdates a refund already recorded in TaxJar. Only the fields you supply are changed.
Action
Validate an AddressChecks a US address and returns TaxJar's corrected version of it, so tax is worked out on a clean address.
Action
Validate a VAT NumberChecks whether a VAT number is valid and returns the business name and address registered against it.
No trigger or action matches that. Ask your agent to add it: it reads the API documentation and builds what you describe.
Each app on its own
Reviews
What our customers say
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Questions
PostStack and TaxJar, answered
What can start an automation from PostStack?
Any of PostStack's 7 triggers in the catalog, including Contact Updated (instant), New Contact (instant), New Inbound Email and New Sent Email (instant). Describe the moment in plain language and your agent picks the right one.
What can your agent do in TaxJar when something happens in PostStack?
Any of TaxJar's 20 actions, including Create a Customer, Create an Order Transaction, Create a Refund Transaction and Update a Customer. Your agent maps the data both ways and tests every scenario before it ships.
Can it also run from TaxJar to PostStack?
TaxJar has no triggers in the catalog today, so automations start in PostStack. If you need the other direction, ask: your agent reads TaxJar's API documentation and adds it.
Do I have to build a connector for PostStack or TaxJar?
No. Both are in the catalog with their triggers and actions. You describe the automation; your agent builds it, tests every scenario and keeps it running.
What happens when something fails?
Your agent works that out for you. It plans the failure paths along with the happy path, then tests every scenario before it ships.
Is there a free plan?
Yes. Every plan includes the agent, including free, and building from your own AI client spends no assistant credits.