What can a signup phone check establish?
Phone validity and line type are different from possession and identity. The current free production route does not request line type. Run four synthetic branches before deciding the next step.
Run the example
Download the ZIP below, extract it and enter the verification_delivery directory. Python 3.10+; no credentials or network calls.
python3 delivery.py phone --branch normal
python3 delivery.py phone --branch unknown
python3 delivery.py phone --branch provider_failure
python3 delivery.py phone --branch otpInputs, outputs and limits
Input: branch. Output: mode, state, valid, line_type, next, otp_sent=false. Unknown/failure goes to bounded recovery or review, not automatic rejection. An OTP recommendation uses the customer’s existing provider and does not send a code.
Test every branch
Engineering tests cover simulated transitions, bindings, duplicate callbacks, restart and timeouts. They do not prove production success, external adoption or Agent superiority.
python3 -m unittest -v test_deliveryDownload runnable synthetic examples
Sources and scope
Based on the alpha contract and source implementation. Live route availability requires separate confirmation.