---
name: scan
description: Scan the code, or a pull request, for the promises its sources make and the tests that do not hold them, answering the model work of the scan as the fulfil skill of `musthold-dp` gives. Use when asked to scan a repository or a pull request, and when `musthold scan --host` exits with code 3.
---

# Scan with a host

`musthold scan --host` stops with exit code 3 while it waits for model work. Each request is a ticket of the scan's own session. The tickets of any other session are not yours.

1. Run `musthold scan --host [<PR>]`, with the pull request number when the user gave one, and the flags the user gave.
2. Exit code 0: the scan finished. Show its report and stop. Exit code 2: show the refusal to the user and stop. Do not loop.
3. Exit code 3: read the line `session scan:<key>` of the output and keep that session. Answer its tickets with steps 4 to 6.
4. If `musthold-s1` is on `PATH` and `.musthold/config.yaml` sets `systemone.endpoint`, run `musthold-s1 drain --module dp --session scan:<key>`. A failure leaves the tickets for the next step.
5. Run `musthold-dp request list --session scan:<key>`. Each line is `<ticket> <role>`. List no other session.
6. Answer each ticket as the skill `musthold-dp-fulfil` gives for a ticket, with the session `scan:<key>` in place of `prove`.
7. Run `musthold scan --host --resume [<PR>]`, with the same pull request number and flags as in step 1. Go back to step 2 with its exit code.