Microsoft Number Checker API Workflow for Automated Checks
The API route for Microsoft numbers is about keeping identity health current. A number that was the MFA receiver in January can be a liability by July:...
Julian works on verification API integrations, batch jobs, CSV workflows, task polling, retry handling, result exports, and developer documentation. His guides explain how teams can integrate verification APIs safely and connect results with internal data systems.
View full author profile →The API route for Microsoft numbers is about keeping identity health current. A number that was the MFA receiver in January can be a liability by July: the account it guards may have changed, the employee may have left, the SIM may have been recycled. The check on a schedule is what keeps the identity layer honest. Microsoft Number Checker is the ZelNum page that supports this job: Microsoft Number Checker.
Quick answer
Submit the list through the API, receive the SMS-capability and status per record, and store it with the role and checked timestamp. Re-run on a schedule and watch the non-SMS share and the drift between runs. The output is the identity-health data the access review runs on.
The API workflow
- Submit the job. One request per batch, carrying the record set and the role field.
- Poll or receive callbacks. Polling is fine at low volume; webhooks pay off when you act on results immediately.
- Store per record. Keep the SMS-capability, status, role, and checked timestamp with the record ID.
- Compare runs. The movement between runs, especially after offboarding waves, is the real output.
Keep the first call small. Submit a handful of records, confirm the response shape, then scale.
The identity-health read
Here is what a quarterly access review looks like over three runs:
| Run | SMS-capable | Not SMS-capable | Invalid | Unknown |
|---|---|---|---|---|
| January | 68% | 16% | 12% | 4% |
| April | 67% | 17% | 12% | 4% |
| July | 64% | 19% | 13% | 4% |
(These figures are illustrative, not a product performance claim.)
The non-SMS slice is creeping up. That is the number that matters for the access review: each point of non-SMS share is a row that cannot do its MFA job. The trend, not the snapshot, is the report.
Webhooks or polling?
Polling on a short interval is simpler for most teams. If you use webhooks, make the callback idempotent: processing the same event twice must not double-charge or double-write. One missed callback should never create a second paid job or overwrite a clean result with a blank one.
Export fields that matter
| Field | Why it matters |
|---|---|
record_id |
Joins the result back to the source. |
role |
Login / recovery / shared / other. |
sms_capable |
The signal that decides the MFA job. |
status / reason |
The verdict and why. |
checked_at |
The timestamp that makes the trend line possible. |
Mistakes to avoid
- Automating the check but not the access review. A non-SMS rate without a replacement queue is decoration. Feed the flags into the account workflow, or the schedule is just a report generator.
- Treating the last run as the current truth. A checked number from March is a guess by July, especially after offboardings.
- Ignoring the non-SMS share. It is the leading indicator of lockouts, and the trend is what lets you act before the lockouts happen.
FAQ
What is the output of the Microsoft API pipeline?
Identity-health data: which numbers can do their MFA and recovery jobs, current enough to act on. The non-SMS share and the drift between runs are the headline numbers.
Why does SMS capability matter?
Because MFA and recovery flows depend on receiving text messages. A number that cannot receive SMS fails the job even when the format is perfect.
How often should the API run?
Monthly is a good baseline, with a re-run immediately after offboarding waves.
Webhooks or polling?
Polling for most teams. It is simpler, has fewer failure modes, and latency is irrelevant at low volume.
What happens to unknown rows?
They wait for a retry. Unknown is not dead, and a later run often resolves it.
Related ZelNum pages
- Bulk Microsoft Number Checker: CSV Upload and Result Export Guide for the file format details.
- Microsoft Number Checker Use Cases for how different teams read the same export.