handler_api.php
handler_api.php is the legacy query-string SMS protocol used by older providers, where actions and responses are plain tokens rather than JSON.
In detail
A compatibility endpoint here speaks it exactly: the same action names, the same parameter names, and the same ACCESS_ and STATUS_ response tokens, so moving an existing script is usually a one-line change of URL and key. It is supported indefinitely, and it is still the worse of the two APIs, because the protocol cannot express idempotency, waiting or structured errors. Use it to migrate, not to build.
Also known as
- handler_api.php
- legacy sms api
- stubs handler