CertZipDL

README.md

@@ -216,6 +216,25 @@ different and only one will suit how you hang them.
 type and the colour option. It is not itself a saved setting — the three fields it fills are what
 get stored, which is why it can appear to "revert" when the same dimensions describe two rolls.
 
+**Ask the printer what it has loaded.** This is the first thing to run when a job is refused:
+
+```bash
+docker compose exec visitor-signin node scripts/printer-status.mjs
+```
+
+It reports the media width, whether the roll is continuous or die-cut, any error the printer is
+holding, and the roll id that matches. `brother_ql`'s network backend only writes to the socket
+and never reads, which is why a refused job still looks like a success — this asks directly.
+
+If the printer will not answer, work through the possibilities one at a time:
+
+```bash
+docker compose exec -it visitor-signin node scripts/print-probe.mjs
+```
+
+It sends one label per roll id and waits for you to say whether anything came out, then moves on.
+The `-it` matters: it asks questions and needs a terminal.
+
 **Diagnostics from the command line.** When the console is not enough:
 
 ```bash