# M91

> An interface for any software or AI to reach a human. An alert raises a
> full-volume interruption on every phone in a channel, breaks through silent
> mode and Do Not Disturb, keeps going until somebody answers, escalates to a
> phone call if nobody does, and records who took responsibility. Email, SMS
> and chat only arrive quietly and wait to be read, which is the wrong
> behaviour when somebody has to act now. The whole integration is one URL: no
> SDK, no API key, no account at the other end.

## Docs

- [Quickstart](https://m91-api.msg91.com/api/public/quickstart.md): One real alert ringing a real phone, verified, in five minutes — with what a correct answer looks like at every step
- [What goes in an alert](https://m91-api.msg91.com/api/public/fields.md): Every field of an alert: what it is for, WHEN a request needs it, and the two mistakes that produce an alert nobody can answer
- [Playbook](https://m91-api.msg91.com/api/public/playbook.md): Where alerting belongs in a codebase, what is worth waking somebody for, human approval inside an agent, and worked integrations
- [M91 API](https://m91-api.msg91.com/api/public/api.md): The contract: every endpoint, every field, the exact response shapes, limits and errors
- [M91 Troubleshooting](https://m91-api.msg91.com/api/public/troubleshoot.md): The exact string to match on, what caused it, and what to do — grouped by where in the lifecycle it went wrong
- [M91: Limitations & Recommendations](https://m91-api.msg91.com/api/public/limitations-and-recommendations.md): What M91 does and does not guarantee, each paired with a recommendation