A campaign describes itself perfectly well without its content being read
What a marketing lead wants from an AI plugged into their sending tool comes down to a few questions. Which campaigns went out, to which lists and on which dates. What is still sitting as a draft. Which templates exist and what they are for. None of those answers requires reading a message or knowing a single person who received it.
Mailjet's shape makes that separation clean. The record of a campaign, a newsletter, a draft or a template lives on the object itself, while its body lives in a separate resource you have to fetch on purpose. The connector reads the record and never calls that resource, for none of the three.
From a campaign, then, in come its subject, its status, the sender's name, the start and end of the send, and the identifier of the list it targets. That identifier links the campaign to a list record already present in your Kastel, without learning anything about its members.
A key pair sees the whole account, so the department is designated by hand
At Mailjet, what separates two scopes is the key pair. It sees the whole of the account it belongs to, with no read permission per campaign and no owner per list. A company that split its brands across several sub-accounts therefore sets up one connection per key pair, and each stays at home. Neither secret in the pair ever leaves the request header, as the security page explains.
Nothing is guessed from there. The connector infers no department from the account's name. It checks that a marketing department has actually been named, that the name is a valid identifier, and that the department genuinely appears in your organisation. Any one of those three checks failing sends the entire account back to waiting for an administrator's decision.
An error reading your organisation produces the same result, rather than a fallback to some default department. That is the behaviour you want from a mechanism that decides who is entitled to read what, and it applies the same way to every source in the catalogue.
Your Kastel describes your sends without reading their content
On a sending tool, the boundary runs between a message's record and its content. Here is the list, as it is written in the connector.
A message body stays out for a reason of shape as much as of caution. It lives in a resource separate from the campaign, one the connector does not call, so the question of filtering it never arises. Your Kastel describes your sending activity; it does not duplicate your content library.
The connector rereads six lists in full on every pass
The six lists are campaigns, newsletters, campaign drafts, contact lists, templates and senders. No Mailjet interface reliably says, across all of those resources, what has changed since last time. Every pass therefore lists them all in full. An unchanged record costs nothing to review, and a new campaign shows up on the following pass rather than the second it goes out.
Templates carry a restriction asked of Mailjet itself. Only the ones your account owns are read; the gallery Mailjet makes available to everyone is excluded at the call, because it says nothing about your company.
One pagination detail deserves naming, because it protects your data rather than our convenience. Mailjet reports the total number of records matching a request. If that total says some remain and a page comes back empty, the connector stops on an error instead of treating its list as complete. An incomplete list taken for a complete one would make live campaigns look like deleted ones.
The questions a marketing lead asks before connecting Mailjet
Will an AI be able to read my contact list?
No. A list comes in as a record, with its name, its address and its subscriber count. Its recipients live behind two Mailjet entry points the connector does not use, and there is no function in its code that reads a contact. What your Kastel knows about a list is what the list is, never who is on it.
Does the text of my newsletters come into your Kastel?
No. The body of a newsletter, a draft or a template is a resource the connector never calls. Your Kastel knows a newsletter exists, what it announced through its subject, where it stands and when it was last modified, without knowing its copy.
What about my open and click rates?
Mailjet keeps its aggregates on a statistics resource this version does not call. The connector keeps counts only when they appear on the campaign itself, and it writes them as totals, never as a log of recipients. When they are absent, the line is absent. Seen from your Kastel, your campaign performance is therefore partial, and we would rather write that here.
What happens to a campaign I delete in Mailjet?
Mailjet marks a deleted campaign or list rather than removing it. The connector treats that mark as a disappearance, stops reading the record, and flags it as gone in your Kastel while keeping it, until an administrator decides to erase it. For a newsletter, a draft, a template or a sender, Mailjet exposes no reliable equivalent mark, so only absence from the list counts, and a status change never passes for a deletion.
What this connector does not do
It sends nothing and creates nothing, no campaign, no draft, no addition to a list, no unsubscribe. The only operation available to it is a read, and there is no write path into your Mailjet account.
It does not give a complete view of your performance. Mailjet's detailed aggregates live on a resource this version does not query, so counts only come in when the campaign carries them itself, and your Mailjet dashboard remains the right place to compare two campaigns. It also reads six lists only, which leaves out the whole transactional side. Messages sent one by one to a person, an order confirmation or a forgotten password, do not come into your Kastel, and no individual send log is read.
A campaign's subject and a newsletter's title are free text. If your team writes a client's name or something sensitive there, it comes in with the record, because the connector does not judge what your people type into a title.
Disconnecting an account empties nothing. The key is deleted and reading stops, but everything already in stays in place and stays readable by the designated department, until an administrator decides to erase it. That separation is deliberate, because a disconnection often happens in a hurry and a lost company memory cannot be recovered.
See how your Kastel is built before you connect a sending tool.
The product page shows what a Kastel holds, how it fills up from your own tools, and how it is decided, source by source, what each AI is entitled to see.
See the product
