Reference & Lookup Data · Integration
Abstract API
Add Abstract API to your product for your customers, and give your AI agents governed access to it.
Abstract API is not one API but a family, each on its own subdomain, such as emailvalidation.abstractapi.com, phonevalidation.abstractapi.com and ipgeolocation.abstractapi.com. The surprise for implementers is that each product issues its own separate key, so a key that works for email validation returns an auth error against phone validation and credential storage has to be per product rather than per account. Keys are passed as an api_key query parameter, which means they end up in access logs unless requests are proxied. Responses are per lookup, with fields such as deliverability and quality score on email checks and carrier and line type on phone checks, and lower tiers enforce a strict per second rate alongside the monthly quota. There is no stored state to sync: every call is a fresh lookup billed against the plan. fastn holds each customer's set of per product keys and keeps calls, quotas and upkeep separated by tenant.
In your product
Embedded for your customers. Per-tenant auth, no per-customer code, maintained by fastn.
Let a customer connect their own Abstract API keys so validation runs on their quota and their plan limits
Validate an email address at signup and block undeliverable or disposable domains before an account is created
Normalise and check phone numbers on entry, storing carrier and line type so SMS sending does not target landlines
Geolocate an IP at login to flag sign ins from unexpected countries in your own risk rules
For your AI agents
Governed, audited access for the agents you build, through the MCP server.
Ask an agent to validate a list of addresses before a send and report which would bounce
Have an agent check a phone number's line type before scheduling an SMS, with the lookup audited per tenant against their quota
Let an agent explain why a specific address was scored as undeliverable using the returned fields
Example prompt
Is this address deliverable, and is the number on file a mobile that can receive SMS?
Set up Abstract API in 4 steps
- 01Enable the Abstract API connector from your fastn dashboard.
- 02Have each customer authorise their own Abstract API 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 Abstract API integration
What you get by embedding it with fastn instead of building it yourself.
- Ship an Abstract API integration without building it. Your customers connect their own Abstract API 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 Abstract API update is not your on-call problem.
- One integration serves your product and your agents. The same governed Abstract API 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.
Used by these teams
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SnowflakeAbstract API integration FAQ
How do I add an Abstract API integration to my product?
Enable the Abstract API connector in your fastn dashboard, then let each customer authenticate their own Abstract API account. fastn handles the OAuth flow, token storage and refresh per tenant, so there is no Abstract API client code in your app and no per-customer branch in your codebase. Setup is 4 steps.
Do my customers each connect their own Abstract API account?
Yes. Every connection is scoped to the individual customer, so each authorises their own Abstract API 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 Abstract API integration?
Yes. The same connection is exposed to your agents through the fastn MCP gateway, with permissions scoped per tenant and every call audited. Ask an agent to validate a list of addresses before a send and report which would bounce
Who maintains the Abstract API integration?
fastn does. When Abstract API 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 Abstract API 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 Abstract API results be cached?
Per tenant, with a window that matches how fast the underlying data actually moves. Abstract API 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 Abstract API integration?
A common starting point: let a customer connect their own Abstract API keys so validation runs on their quota and their plan limits. 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 Abstract API integration cost?
It is included. Pricing is based on connected accounts, not on how many connectors you enable, so adding Abstract API does not change your per-connector cost. You can start free with 3 connected accounts.
Add Abstract API to your product
Start free with 3 connected accounts. No sales call required, and no per-customer integration code.