Finance & ERP · Integration
Chaser
Add Chaser to your product for your customers, and give your AI agents governed access to it.
Chaser automates accounts receivable chasing, and its open API is on a separate host at openapi.chaserhq.com with just four resources: customers, invoices, credit notes and organizations. Auth is HTTP Basic with an API key as the username and a secret as the password, both generated under Organization Settings then Integrations, which is unusual enough that bearer-token clients need reconfiguring. Order matters: a customer must exist before its invoices or credit notes can be pushed, because the relationship is keyed on your external customer ID rather than a Chaser ID. Invoice status drives visibility in the product, so AUTHORISED invoices are chased, PAID ones remain visible for six months and then drop away, and DRAFT invoices are hidden entirely, which surprises implementers who push drafts and see nothing. The API exists for organisations whose ledger Chaser does not natively integrate with, so it pushes data one way rather than reconciling against an accounting connection, and dates must be ISO 8601. fastn holds each customer's key and secret, keeps the customer-before-invoice ordering right, and maintains the connection as Chaser versions the API.
In your product
Embedded for your customers. Per-tenant auth, no per-customer code, maintained by fastn.
Let a customer connect their own Chaser account so invoices raised in your product are chased without a CSV export.
Push credit notes as they are issued so Chaser stops chasing an amount that has already been credited.
Update invoice status to PAID from your product the moment payment settles, so reminders stop the same day.
Read chasing activity back into your app so account managers can see what a customer has already been sent.
For your AI agents
Governed, audited access for the agents you build, through the MCP server.
Let an agent push a batch of new invoices for an existing customer and report what was accepted, with the invoice references and tenant written to a per-tenant audit log.
Have an agent list AUTHORISED invoices past their due date and summarise total exposure by customer.
Let an agent check for invoices sent to Chaser as DRAFT and explain why they are not being chased.
Example prompt
Which overdue invoices is Chaser currently chasing, and what is the total outstanding by customer?
Set up Chaser in 4 steps
- 01Enable the Chaser connector from your fastn dashboard.
- 02Have each customer authorise their own Chaser account, so calls run under their credentials rather than a shared key.
- 03Decide which invoices, payments and vendors your product needs, map those fields, then enable the actions and triggers you want.
- 04Call it from your product and expose it to your agents through the same governed connection.
Why teams use the Chaser integration
What you get by embedding it with fastn instead of building it yourself.
- Ship a Chaser integration without building it. Your customers connect their own Chaser account inside your product and work their invoices, payments and vendors there, with no per-customer code on your side.
- Handle the part that actually costs time: financial writes must be idempotent and reconcilable, because a duplicate is an accounting problem rather than a bug. fastn owns the auth, token refresh, rate limits, pagination and breaking-change fixes, so a Chaser update is not your on-call problem.
- One integration serves your product and your agents. The same governed Chaser connection powers in-product features and gives AI agents scoped, audited access, so you move financial records without hand-keying them between systems without wiring it twice.
Used by these teams
Compare with
NetSuite
QuickBooks
XeroOften used alongside
Tools the same teams tend to run next to Chaser, across other categories.
Shopify
Stripe
BigCommerce
AfterShipChaser integration FAQ
How do I add a Chaser integration to my product?
Enable the Chaser connector in your fastn dashboard, then let each customer authenticate their own Chaser account. fastn handles the OAuth flow, token storage and refresh per tenant, so there is no Chaser client code in your app and no per-customer branch in your codebase. Setup is 4 steps.
Do my customers each connect their own Chaser account?
Yes. Every connection is scoped to the individual customer, so each authorises their own Chaser account and only ever sees their own invoices, payments and vendors. That per-tenant isolation is the point of an embedded integration: you support the long tail of customer setups without maintaining an integration per customer.
Can AI agents use this Chaser integration?
Yes. The same connection is exposed to your agents through the fastn MCP gateway, with permissions scoped per tenant and every call audited. Let an agent push a batch of new invoices for an existing customer and report what was accepted, with the invoice references and tenant written to a per-tenant audit log.
Who maintains the Chaser integration?
fastn does. When Chaser changes an endpoint, deprecates a field or alters its auth, the fix lands in the connector rather than in your backlog, and your customers' connections keep working.
Is the Chaser integration safe for financial writes?
Writes are idempotent, so a retry after a timeout does not post a document twice, and every call is logged per tenant so an entry can be traced back to the event that created it. That matters more in finance than anywhere else, because a duplicate is a number somebody has to explain.
Can it handle each customer's own chart of accounts?
Yes. ERP deployments are configured to the business, so account structures, required fields and fiscal calendars differ per customer. Those are mapped per tenant as configuration, not hard-coded.
What about Chaser rate limits during a first import?
Backfills are throttled deliberately. ERP limits are often account-wide rather than per-integration, so an unthrottled import can exhaust a customer's allowance and disrupt their other integrations.
What can I build with the Chaser integration?
A common starting point: let a customer connect their own Chaser account so invoices raised in your product are chased without a CSV export. Teams also use it for the other use cases listed above, and expose it to agents for governed reads and writes.
How much does the Chaser integration cost?
It is included. Pricing is based on connected accounts, not on how many connectors you enable, so adding Chaser does not change your per-connector cost. You can start free with 3 connected accounts.
Add Chaser to your product
Start free with 3 connected accounts. No sales call required, and no per-customer integration code.