Reference & Lookup Data · Integration
MxToolbox
Add MxToolbox to your product for your customers, and give your AI agents governed access to it.
Embed an MxToolbox integration so your product can diagnose a domain's mail and DNS health without you writing lookup logic against a dozen sources. MxToolbox runs DNS, MX, SMTP and blacklist checks and can monitor a host continuously, and alerts arrive as events rather than something your product polls for, so a deliverability problem surfaces in near real time. fastn handles credentials, retries, result normalisation and deduplication per check, so a flapping monitor does not create a queue of identical records for your users to sift through.
In your product
Embedded for your customers. Per-tenant auth, no per-customer code, maintained by fastn.
Let your product run DNS, MX, SMTP and blacklist lookups for a customer's domain on demand.
Create and manage monitors so a customer's mail domain is watched continuously from inside your product.
Surface blacklist listings and their reasons where the person who can fix deliverability actually works.
Deduplicate alerts per check so a flapping monitor does not spam your users.
For your AI agents
Governed, audited access for the agents you build, through the MCP server.
An agent runs a lookup and explains which record is misconfigured and what to change.
An agent reacts to a blacklist alert and assembles the context needed to request delisting.
An agent checks a domain's SPF, DKIM and DMARC records before a send is attempted.
Example prompt
Check this domain's mail configuration and blacklist status, then explain what to fix first.
Set up MxToolbox in 4 steps
- 01Open the MxToolbox connector from your fastn dashboard.
- 02Connect the MxToolbox credentials each customer uses, stored encrypted per tenant.
- 03Choose the lookups and monitors your product runs, then enable alert triggers.
- 04Call them from your product, or expose them to an agent through the MCP server.
Why teams use the MxToolbox integration
What you get by embedding it with fastn instead of building it yourself.
- Ship a MxToolbox integration without building it. Your customers connect their own MxToolbox 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 MxToolbox update is not your on-call problem.
- One integration serves your product and your agents. The same governed MxToolbox 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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SnowflakeMxToolbox integration FAQ
How do I add a MxToolbox integration to my product?
Enable the MxToolbox connector in your fastn dashboard, then let each customer authenticate their own MxToolbox account. fastn handles the OAuth flow, token storage and refresh per tenant, so there is no MxToolbox client code in your app and no per-customer branch in your codebase. Setup is 4 steps.
Do my customers each connect their own MxToolbox account?
Yes. Every connection is scoped to the individual customer, so each authorises their own MxToolbox 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 MxToolbox integration?
Yes. The same connection is exposed to your agents through the fastn MCP gateway, with permissions scoped per tenant and every call audited. An agent runs a lookup and explains which record is misconfigured and what to change.
Who maintains the MxToolbox integration?
fastn does. When MxToolbox 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 MxToolbox 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 MxToolbox results be cached?
Per tenant, with a window that matches how fast the underlying data actually moves. MxToolbox 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 MxToolbox integration?
A common starting point: let your product run DNS, MX, SMTP and blacklist lookups for a customer's domain on demand. 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 MxToolbox integration cost?
It is included. Pricing is based on connected accounts, not on how many connectors you enable, so adding MxToolbox does not change your per-connector cost. You can start free with 3 connected accounts.
Add MxToolbox to your product
Start free with 3 connected accounts. No sales call required, and no per-customer integration code.