Reference & Lookup Data · Integration
Bouncer
Add Bouncer to your product for your customers, and give your AI agents governed access to it.
Bouncer verifies deliverability at api.usebouncer.com, authenticating with an x-api-key header; a call to /v1/email/verify without it returns a clean 401, which makes credential testing cheap. Single verification is synchronous, but batch work is not: you post a list to the batch endpoint, receive a job id, poll its status until it completes, then download the results, so any integration needs job state rather than a request-response loop. The result is not a boolean. Each address comes back with a status such as deliverable, risky, undeliverable or unknown, plus a reason that distinguishes an accept-all domain from a full mailbox from a disposable provider, and treating risky as a hard fail is the most common way teams silently discard good addresses. Verification consumes credits per address, so re-verifying a list you already checked is a billing event and results should be cached against the address. There is also a separate toxicity check for addresses associated with complaints and traps, which is a different signal from deliverability and should not be merged into the same field. fastn holds each customer's Bouncer key, tracks their batch jobs and keeps the polling logic out of your codebase.
In your product
Embedded for your customers. Per-tenant auth, no per-customer code, maintained by fastn.
Let a customer connect their own Bouncer key so verification runs on their credits, not yours
Verify an address at signup before it enters your customer's mailing list
Run an imported list through a batch job and show progress in your UI while it completes
Store the status and reason alongside each contact so suppression rules can be explained later
For your AI agents
Governed, audited access for the agents you build, through the MCP server.
Let an agent verify a specific address on request and report the reason code, not just pass or fail
Have an agent batch-check a segment before a send and report the credit cost, audited per tenant
Let an agent flag contacts that moved from deliverable to undeliverable since the last check
Example prompt
Is this address safe to send to, or is it on an accept-all domain?
Set up Bouncer in 4 steps
- 01Enable the Bouncer connector from your fastn dashboard.
- 02Have each customer authorise their own Bouncer 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 Bouncer integration
What you get by embedding it with fastn instead of building it yourself.
- Ship a Bouncer integration without building it. Your customers connect their own Bouncer 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 a Bouncer update is not your on-call problem.
- One integration serves your product and your agents. The same governed Bouncer 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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SnowflakeBouncer integration FAQ
How do I add a Bouncer integration to my product?
Enable the Bouncer connector in your fastn dashboard, then let each customer authenticate their own Bouncer account. fastn handles the OAuth flow, token storage and refresh per tenant, so there is no Bouncer client code in your app and no per-customer branch in your codebase. Setup is 4 steps.
Do my customers each connect their own Bouncer account?
Yes. Every connection is scoped to the individual customer, so each authorises their own Bouncer 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 Bouncer 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 specific address on request and report the reason code, not just pass or fail
Who maintains the Bouncer integration?
fastn does. When Bouncer 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 a Bouncer 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 Bouncer results be cached?
Per tenant, with a window that matches how fast the underlying data actually moves. Bouncer 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 Bouncer integration?
A common starting point: let a customer connect their own Bouncer key so verification runs on their credits, 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 Bouncer integration cost?
It is included. Pricing is based on connected accounts, not on how many connectors you enable, so adding Bouncer does not change your per-connector cost. You can start free with 3 connected accounts.
Add Bouncer to your product
Start free with 3 connected accounts. No sales call required, and no per-customer integration code.