When an agent shows you something

An agent working for you can ask Nightdesk to show you something — a screenshot it took, a diagram it rendered, a clip, a PDF, or a web page such as a pull request. Nightdesk opens it as a tab beside that agent’s session and brings the window forward.

Attaching it to the agent that asked is the point: nothing ever appears from nowhere. Whatever has arrived, the agent it belongs to tells you who put it there.

Where it lands

Nightdesk tries these in order:

1. The agent that asked, when it said which session it was. Concierge always resolves to Concierge.
2. An agent that already has that pull request open, when a PR link is what is being shown.
3. The agent you have selected.
4. Your browser, when none of the above is available.

That last step is deliberate: a URL is never swallowed. If Nightdesk has nowhere to put it — an empty fleet, or an open it could not complete — the link still opens, in the browser it was headed for anyway.

The agent is told what happened

Every outcome comes back to the agent as something it can read and pass on to you:

• Shown in a tab — the ordinary case.
• Opened in your browser — Nightdesk had nowhere to hang the tab. An agent that gets this answer is expected to tell you so, rather than report that you have seen it.
• Refused, with the reason and what to do about it.

Anything Nightdesk will not show is refused out loud. Nothing is quietly sent somewhere else and reported as a success.

What is refused

Images and PDFs are accepted up to 64 MiB, video up to 2 GiB; something over the ceiling is refused with the ceiling quoted, so the agent knows what it was measured against. Anything that is not one of those shapes, or a web page, is refused rather than guessed at.

Files in folders macOS protects

macOS guards ~/Desktop, ~/Documents, ~/Downloads, iCloud Drive, and mounted volumes: an app needs your consent to read them. Nightdesk does not pre-emptively refuse a file in one of those places — it lets macOS ask you, because being asked is the only way that consent is ever granted.

When a file there is missing, the refusal still has to name the right cause, so Nightdesk asks one more question before answering: is the guarded folder itself readable? If it is, the file is genuinely not there, and the refusal says exactly that. If it is not, the refusal raises permissions instead.

A mounted volume that stops answering is told both stories — consent still pending, or a share that has gone away — because from the outside those two are indistinguishable, and on a network share the second is often the truth.

A link you paste in yourself

The same routing catches a bare open of a pull request URL typed or pasted into a Nightdesk terminal by hand, which no agent’s tool call would ever cover. It lands as a tab the same way, and if it cannot, it opens in your browser. What Nightdesk writes to your machine describes the small script behind that, and how to remove it.