Reference & Lookup Data · Integration
AddressZen
Add AddressZen to your product for your customers, and give your AI agents governed access to it.
AddressZen splits address capture into two calls: /v1/autocomplete/addresses returns ranked partial matches, and you then retrieve the selected suggestion to get the full structured record, so nothing useful comes back from the suggest step alone. Authentication is by api_key, and the service answers with numeric application codes inherited from the Ideal Postcodes stack rather than plain HTTP semantics, so an invalid key comes back as code 4010 and an unknown key as 4042 even though both are 401 and 404 shaped. A key can be pinned to a list of allowed URLs, which is why calls that work from a server start failing the moment they are moved into a browser, and /v1/keys/{key} is the endpoint that tells you the quota and configuration behind that behaviour. Beyond lookup there are verification calls for US deliverability and separate phone and email validation endpoints, all metered off the same key. fastn stores each customer's AddressZen key, keeps the allowed URL and quota state visible, and handles rotation without you writing per tenant key plumbing.
In your product
Embedded for your customers. Per-tenant auth, no per-customer code, maintained by fastn.
Let a customer connect their own AddressZen key so address autocomplete in your product is billed and metered against their account, not yours
Validate addresses captured in your signup and checkout forms before they reach the customer's downstream systems
Run a periodic cleanup that re verifies stored addresses and flags ones that no longer verify as deliverable
Check phone and email fields at capture time using the same key so contact data quality is enforced in one place
For your AI agents
Governed, audited access for the agents you build, through the MCP server.
Let an agent verify a single address a support rep pasted in and return the standardised record without giving it the raw key
Have an agent read key usage and quota so it can warn a tenant before their lookup allowance runs out
Audit per tenant which addresses an agent verified, so lookup spend can be attributed back to the account that caused it
Example prompt
Is the delivery address on this order verifiable, and what is the standardised version?
Set up AddressZen in 4 steps
- 01Enable the AddressZen connector from your fastn dashboard.
- 02Have each customer authorise their own AddressZen account, so calls run under their credentials rather than a shared key.
- 03Decide which lookups, results and reports 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 AddressZen integration
What you get by embedding it with fastn instead of building it yourself.
- Ship an AddressZen integration without building it. Your customers connect their own AddressZen account inside your product and work their lookups, results and reports there, with no per-customer code on your side.
- Handle the part that actually costs time: these are metered read sources, so an uncached lookup on every page view burns the customer's allowance. fastn owns the auth, token refresh, rate limits, pagination and breaking-change fixes, so an AddressZen update is not your on-call problem.
- One integration serves your product and your agents. The same governed AddressZen connection powers in-product features and gives AI agents scoped, audited access, so you answer questions from an authoritative outside source without holding that data yourself without wiring it twice.
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SnowflakeAddressZen integration FAQ
How do I add an AddressZen integration to my product?
Enable the AddressZen connector in your fastn dashboard, then let each customer authenticate their own AddressZen account. fastn handles the OAuth flow, token storage and refresh per tenant, so there is no AddressZen client code in your app and no per-customer branch in your codebase. Setup is 4 steps.
Do my customers each connect their own AddressZen account?
Yes. Every connection is scoped to the individual customer, so each authorises their own AddressZen account and only ever sees their own lookups, results and reports. 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 AddressZen 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 verify a single address a support rep pasted in and return the standardised record without giving it the raw key
Who maintains the AddressZen integration?
fastn does. When AddressZen 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.
Whose credentials does an AddressZen lookup run under?
Each customer's own. Quota and cost land on the customer that caused them rather than on a shared key you have to meter and re-bill, and one heavy customer cannot exhaust another's allowance.
How should AddressZen results be cached?
Per tenant, with a window that matches how fast the underlying data actually moves. AddressZen is a read source rather than a system of record, so the same query returns the same answer until the source changes, and caching is the difference between a sustainable integration and one that exhausts a customer's allowance on a busy page.
What can I build with the AddressZen integration?
A common starting point: let a customer connect their own AddressZen key so address autocomplete in your product is billed and metered against their account, not yours. 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 AddressZen integration cost?
It is included. Pricing is based on connected accounts, not on how many connectors you enable, so adding AddressZen does not change your per-connector cost. You can start free with 3 connected accounts.
Add AddressZen to your product
Start free with 3 connected accounts. No sales call required, and no per-customer integration code.