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+---
+name: Notifying the user
+description: Use when you want to reach the user on their phone — work finished while they were away, something needs a decision, or you are about to ask them to paste you a credential so you can tell them something.
+version: 1
+---
+
+**You have a key for this. `$OFFICER_AGENT_KEY`.** It is in your environment, minted for this session, and
+it can do exactly one thing: send a notification to the person you are working for. Never ask them to paste
+you an API key so you can tell them something — you already have the only kind you should have.
+
+```
+curl -X POST "$OFFICER_API_URL/api/notify/_officer/notify" \
+  -H "Authorization: Bearer $OFFICER_AGENT_KEY" -H "Host: $OFFICER_API_HOST" \
+  -H "content-type: application/json" \
+  -d '{"code":"officer/core:message","title":"<a few words>","body":"<one sentence>"}'
+```
+
+No `userId` — the key says who you are, and it can only reach that person. `title` and `body` are yours to
+write. It arrives on their phone.
+
+**This is not the same channel as your harness's own push tool.** That one refuses to interrupt a terminal
+the user is sitting at, which is right for it and wrong for this: a notification from here is for reaching
+somebody who is NOT looking, and it goes whether they are at the desk or not.
+
+**So send few, and only what needs them.** A notification is an interruption. Something finished that they
+asked for and will see anyway is not worth one; a decision you are blocked on, or a failure they would
+otherwise find tomorrow, is. Being told what worked trains somebody to stop reading, and then the one that
+mattered arrives in a queue they no longer open.
+
+**What you write goes through Apple and Google to reach a lock screen.** Almost everything else in Officer
+travels as a code the device renders itself, so nothing readable leaves the machine. This is the exception,
+and the judgement is yours: what you did, a count, a name they chose — fine. The contents of what you were
+reading, a filename, a sender, a credential, anything told to you in confidence — never. When in doubt, say
+that something happened and let them come and look.
+
+If the key is absent, say so plainly rather than reaching for another way in. It means minting one failed,
+which is worth knowing about.