How to use Clever data with Kastr (and what Clever does not hand over)
Kastr is not in the Clever application library. There is no Clever Instant Login, no Badges, no one-click connection. What you can do is use the rostering data your district already publishes to Clever — and understand, before you commit, why a Clever-only feed frequently cannot power SMS or voice.
| Clever object | Typical coverage | Kastr destination | Good enough on its own? |
|---|---|---|---|
| districts | Complete | Root organisation | Yes |
| schools | Complete | Child organisations in the hierarchy | Yes |
| students | Complete | Person records with student roles | Yes |
| teachers / staff | Complete | Person records with effective-dated staff roles | Yes |
| sections | Complete | Stored; not yet an audience filter | Stored, unusable today |
| contacts — names and relationship | Shared only if enabled | Guardian edges | Depends entirely on the share |
| contacts — phone numbers | Frequently withheld | Contact points | This is the gap |
| contacts — email | More often shared than phone | Contact points | Email-only reach is not reach |
| guardian language preference | Rarely present | Language preference | Take it from the SIS |
| educational rights / restrictions | Not modelled | — | Take it from the SIS |
"Frequently withheld" is not a criticism of Clever. Guardian contact sharing is a per-district, per-application decision that a district administrator has to make explicitly, and the sensible default for most applications is not to share it. The problem is that a communications platform is the one category where it is the whole point, and nobody discovers the gap until week two.
Two honest routes
Route one: Clever Secure Sync to storage you control. Clever can deliver rostering files to a district-controlled destination. From there the pattern is identical to every other page in this cluster — a cron job POSTs the file to /api/v1/roster/sync. Kastr holds no Clever credential, the district holds everything, and the security review is short.
Route two: a district-run pull from Clever's API. If your team would rather write a script than schedule a delivery, pull the objects you need, shape them, POST them. Same endpoint, same diff engine, more code you own.
What is not available: a Clever application listing that a district administrator can authorise in the Clever dashboard, which is the flow most districts assume when they see a Clever logo on a vendor site. Kastr does not have one. Every route here is a file your district produces and sends.
Either way, run --dry-run first. The ledger prints every add, change and withdrawal before anything is written, and the number to look at hardest is students with at least one SMS-capable contact point.
The guardian-data gap, in detail
This is the section that matters, and it is why this page exists.
Clever's rostering feed was designed to get students, teachers and sections into learning applications. Those applications do not need to phone a parent. Guardian contact data therefore sits behind an explicit sharing decision, made per district and per application, and in a great many districts it is simply never enabled — often for entirely sound privacy reasons.
The result is a specific and predictable failure. A district connects a communications platform through Clever, sees a full roster of students and classes, declares the integration complete, and then discovers at the first weather closure that a large share of families have no phone number attached. The rostering worked perfectly. The communications did not.
The check to run before you commit to a Clever-only topology. Take your Clever share configuration and count how many guardian phone numbers it actually exposes. Not how many exist in the SIS — how many cross the boundary. If the answer is zero, or a small fraction, a Clever-only roster cannot power SMS or voice, and no vendor's software fixes that. Ask any vendor showing you a Clever logo this exact question and watch how quickly they can answer it.
The fallback that works. Take students, staff, schools and sections from Clever, because that part is clean and already running. Take guardians, phone numbers, language and rights flags from a small direct SIS extract — PowerSchool, Infinite Campus and the rest all produce one in a few hours. Two files, one POST, and a roster that can actually reach a family.
No Instant Login, and why that is not the loss it sounds like
Kastr has no Clever Instant Login, no Clever Badges, no SSO of any kind. Magic link is the only authentication in the product, for staff and families alike: 32 random bytes, a fifteen-minute lifetime, single use, consumed atomically so a prefetching mail scanner cannot burn it, bound to the device that requested it, and issued whether or not the email exists so the endpoint cannot be used to enumerate accounts.
Here is the reasoning, which you are free to disagree with. The largest user population of a school communications platform is guardians, and guardians do not hold district-issued accounts. A district with 12,000 students has perhaps 20,000 guardians and 900 staff. Clever Instant Login solves authentication for students and staff — a small minority of the people this system exists to reach — and does nothing at all for the majority.
Where it costs you: staff sign in with a link in their email rather than through the portal they already have open, which is a genuine daily-use friction, and there is no MFA to point at in a security review. We are not going to dress that up. What we offer a security reviewer instead is a token design they can test in ten minutes: request a link twice and confirm the first is dead, open it in a different browser and confirm it fails, request a link for an address that does not exist and confirm the response is identical.
Cost, and what a broker does not change
Using Clever does not change what Kastr costs. There is no integration fee, no connector charge and no premium tier that unlocks rostering. One price per student per year — $3.50 under 5,000 students, $3.25 to 14,999, $3.00 above — with every feature included and the rate fixed for 36 months under §3.2, capped afterwards at the lesser of CPI-U or 5%.
What a broker does change is who owns the failure. If the Clever feed stops, Kastr sees no file and reports no sync. Point your existing monitoring at the job the same way you would any overnight batch, and set an alert on "no successful sync in 36 hours" rather than trusting silence.
One more thing worth knowing when a broker sits in the path: Kastr's outbound webhooks can tell your own systems when a sync completes, aborts or classifies more changes than a threshold you set. The signature is an HMAC over the timestamp and raw body, delivery retries on a fixed schedule, and an endpoint that fails ten times consecutively is disabled automatically rather than retrying forever. The API page has the verification recipe.
Questions people actually ask
Is Kastr available in the Clever app library?
No. There is no Kastr listing in the Clever library, so there is no application a district administrator can authorise from the Clever dashboard. What works is Clever Secure Sync delivering rostering files to storage your district controls, or a district-run pull from Clever's API, with a job you own POSTing the result to our roster endpoint.
Can families sign in to Kastr with Clever?
No. There is no Clever Instant Login, no Badges and no SSO of any kind. The only authentication in Kastr is a magic link — single use, fifteen-minute lifetime, device-bound. The reasoning is that guardians outnumber students and staff and hold no district accounts, so portal SSO solves authentication for a minority of the people the system exists to reach.
Does Clever give Kastr guardian phone numbers?
Only if your district has explicitly enabled contact sharing, and many have not. Guardian contact data sits behind a per-district, per-application decision, and the default in most deployments is not to share it. Count how many numbers your share configuration actually exposes before you plan a Clever-only topology, because a roster without phone numbers cannot send SMS or voice.
If Clever cannot supply guardian contacts, what is the recommended topology?
Take students, staff, schools and sections from Clever, since that feed is already clean and running, and take guardians, phone numbers, language preference and rights flags from a small direct SIS extract. Two files, one POST. It is a few hours of work and it is the difference between a roster and a reachable roster.
Does using Clever change what Kastr costs?
No. There is no integration fee, no per-connector charge and no tier that unlocks rostering. The price is per student per year, every feature included, fixed for 36 months, with year four onwards capped at the lesser of CPI-U or 5% in the contract itself rather than in a sales conversation.
One price. Every feature. Locked for three years.
$3.50 per student per year under 5,000 students. No tiers, no add-on modules, no per-message fees. Published on the site because you should not have to book a call to learn a price.