[quickbeard]

Clicking Work before you have a sandbox opens the Add sandbox dialog — Work with no sandbox is a dead end, so the gate asks for one first. But that dialog arrives unbidden and said nothing about why it was there: the first thing it asked for was a name, for something the user had not yet decided they wanted.

It now leads with the reason:

Work runs each session inside a sandbox, so it needs one before you can use it. Cancel to stay on Code.

The second sentence is the part that isn't guessable. Cancelling doesn't drop you into an empty Work side — it leaves you on Code, which is what the gate already does but never said.

Where it appears, and where it doesn't

DialogAddSandbox gains an optional requiredForWork, and exactly one of the three call sites passes it:

Call site	Explanation	Why
Work gate (workspace/tabs.tsx)	yes	The dialog opened on its own; it has to say why
Settings → Add server → Add sandbox	no	A deliberate "add a sandbox" — as you asked
Work empty-state button	no	Sits directly beneath "No sandbox yet. Create one to work in an isolated environment." — repeating it in the dialog would be noise

That third one is a judgement call rather than something you specified: it is on the Work side, so a stricter reading of "clicking Work" would include it. Say the word and I'll pass the flag there too.

Verified in the running app

Driven over the DevTools protocol with zero sandboxes configured, which is the state that triggers the gate:

• Clicking Work → dialog opens with the intro (text asserted from the DOM, not just eyeballed).
• Settings → Add server → Add sandbox → hasIntro: false, dialog unchanged.

Screenshot confirms the line sits above the name field, ahead of the existing per-field hints, so the dialog reads reason-first then field-by-field.

Spanish translated to match, using the localised tab names (Trabajo / Código). bun typecheck clean.

🤖 Generated with Claude Code