Marketing Automation · Integration
Kit
Add Kit to your product for your customers, and give your AI agents governed access to it.
Kit, which was ConvertKit until 2024, organises everything around tags rather than lists, and that one decision shapes how you integrate with it. A subscriber has tags, custom fields and a status, and almost anything worth automating is expressed as applying or removing a tag: a tag can put somebody into a sequence, pull them out of one, and is usually the trigger a creator has already built their own automations around. Forms and sequences are separate objects a subscriber can be added to directly, for the cases where a tag is not the right seam. Version four of the API brought OAuth alongside the older key, so an app serving many creators authorises each account properly instead of asking people to paste a secret into a settings page. Broadcasts can be created and sent from outside, which is what makes a product-driven newsletter possible. Each creator connects their own account, so sends come off their subscriber count.
In your product
Embedded for your customers. Per-tenant auth, no per-customer code, maintained by fastn.
Let each creator authorise their own Kit account with OAuth, so your product never holds a pasted secret.
Apply and remove tags as the way to drive automation, since that is the seam a creator's existing sequences already listen to.
Add a subscriber to a form or a sequence directly for the cases where a tag is not the right trigger.
Create and send a broadcast from your product, so a newsletter is assembled where the content it describes already lives.
For your AI agents
Governed, audited access for the agents you build, through the MCP server.
An agent tags a subscriber after a qualifying event, with the tag and the account recorded.
An agent reports which sequences a subscriber is in and what they are due to receive next.
An agent drafts a broadcast and leaves the send to a person.
Example prompt
Which subscribers earned the paid-customer tag this month, and are any of them still in the trial sequence?
Set up Kit in 4 steps
- 01Enable the Kit connector in your fastn dashboard.
- 02Have each creator authorise their own Kit account with OAuth, so nobody pastes a secret into your product.
- 03Map that account's tags, custom fields, forms and sequences, then decide which of your product's events apply which tag.
- 04Call it from your product and expose the same connection to your agents through the MCP gateway.
Why teams use the Kit integration
What you get by embedding it with fastn instead of building it yourself.
- Ship a Kit integration without building it. Your customers connect their own Kit account inside your product and work their campaigns, segments and subscribers there, with no per-customer code on your side.
- Handle the part that actually costs time: engagement data arrives as a high-volume event stream, so ordering and deduplication matter. fastn owns the auth, token refresh, rate limits, pagination and breaking-change fixes, so a Kit update is not your on-call problem.
- One integration serves your product and your agents. The same governed Kit connection powers in-product features and gives AI agents scoped, audited access, so you trigger and measure campaigns from inside your product without wiring it twice.
Used by these teams
Compare with
Mailchimp
ActiveCampaign
FlodeskOften used alongside
Tools the same teams tend to run next to Kit, across other categories.
Salesforce
HubSpot
Pipedrive
Zoho CRMKit integration FAQ
How do I add a Kit integration to my product?
Enable the Kit connector in your fastn dashboard, then let each customer authenticate their own Kit account. fastn handles the OAuth flow, token storage and refresh per tenant, so there is no Kit client code in your app and no per-customer branch in your codebase. Setup is 4 steps.
Do my customers each connect their own Kit account?
Yes. Every connection is scoped to the individual customer, so each authorises their own Kit account and only ever sees their own campaigns, segments and subscribers. 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 Kit 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 tags a subscriber after a qualifying event, with the tag and the account recorded.
Who maintains the Kit integration?
fastn does. When Kit 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.
Can I trigger a Kit campaign from an event in my product?
Yes. Product events can start a campaign, add a contact to a segment, or enrol someone in a journey, so lifecycle messaging follows what a user actually did rather than a nightly export.
Can I read engagement results back from Kit?
Yes. Results come back scoped per tenant, so your product can act on them without one customer's data mixing with another's. What you get depends on the channel: opens, clicks, bounces and unsubscribes where there are sends, and impressions, spend and conversions where there are campaigns.
What can I build with the Kit integration?
A common starting point: let each creator authorise their own Kit account with OAuth, so your product never holds a pasted secret. 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 Kit integration cost?
It is included. Pricing is based on connected accounts, not on how many connectors you enable, so adding Kit does not change your per-connector cost. You can start free with 3 connected accounts.
Add Kit to your product
Start free with 3 connected accounts. No sales call required, and no per-customer integration code.