Every turn in a project starts at the composer — the input at the foot of the project screen (and on the home screen for a new project). What you put in it decides the run more than any setting: this page covers its controls and how to brief the agent well.
The controls
- Input — the brief itself. One message per turn; Enter sends, Shift+Enter breaks a line.
- Agent chip — the CLI and model this turn runs on (Claude Code · Default). Click to switch agents or models per run.
- Effort — how hard the agent works the problem; Fast for iteration, higher for polish.
- Quality mode — Fast, Reviewed or Council — how the result is checked before it lands (see Quality modes).
- Attach — drop files or video references into the turn (see Attachments and video references).
- History — restore an earlier state of the project (see History and restore).
- Send — kicks the turn off; while the agent works it flips to a busy state.
Brief anatomy
A good brief carries three things, usually in one or two sentences:
- What it is — "a landing page", "the pricing section", "an empty state"
- Who or what it's for — "for a coffee subscription", "for first-time users"
- The feel — "dark, editorial, confident type", "quiet, expensive-feeling"
Skip the spec-sheet details (exact pixels, exact hex) — the design system owns those decisions, and overriding them piecemeal produces worse results than a clear direction applied consistently.
Follow-ups are steering, not restarts
After the first turn the composer is a conversation. Each follow-up edits the same files in place — "swap the hero image for a product shot" or "make the nav feel lighter" — so you refine instead of regenerating. For a different direction entirely, branch a version or run variants instead.
Tip: When a fix is about a specific element, don't describe it — pin it. ⌥-click the element in the preview and the comment lands attached to the exact node. See Pick, comment and draw.
Pins, comments and references ride along
Comments you placed with ⌥-click, Designer Talk notes and attached files are folded into the next brief automatically — the agent sees the steering in context, not as a bare instruction. Resolve or clear pins when a fix lands so the next turn isn't re-reading stale notes.