Comments

Comment on a thread the way you’d comment on a document: select a span of text in your own message or the agent’s, and attach a note to it. The comment stays with the text it’s about. Comments also work on code, in the file tabs and diff views of the Changes tab.

Paste images into a comment to attach them inline, including in file and diff comments.

Add a comment

There are two ways to start a comment on the agent’s output:

1. Click in the output or select a passage, then start typing. Delta creates a draft comment at the cursor or around the selection instead of changing the agent’s response.
2. Select a passage, then choose Edit > Comment on Selection. You can also press Cmd+Option+M on macOS or Ctrl+Alt+M on Linux and Windows.

Comments support replies, so a comment can grow into a small review discussion between you and the agent or among collaborators in a shared thread. Typing in a draft comment edits it. After a comment is delivered, typing inside it starts a reply, including when the delivered comment is your own.

Comment on files and diffs

To leave feedback on the code itself rather than the conversation, comment in the Changes tab. In both file tabs and diff views, select code and start typing: comment mode is on by default, so typing creates a comment rather than editing the file. You can also press Cmd+Option+M on macOS or Ctrl+Alt+M on Linux and Windows, the same shortcut as in the transcript, or right-click the selection and choose Comment.

To edit a file directly instead, click the speech-bubble toggle in the file toolbar: filled means typing creates comments, outlined means typing edits the file. You can also press Cmd+Option+C on macOS or Ctrl+Alt+C on Linux and Windows while the file tab is focused. Your choice applies across threads and is remembered when you restart Delta.

Sending a comment follows the same keys as sending a message: Cmd+Enter on macOS or Ctrl+Enter on Linux and Windows by default, or Enter if you turned the Send With Modifier setting off. Sending from a file or diff comment delivers it without returning to the composer. Once delivered, these comments collapse into indicators in the gutter; click an indicator, or press Cmd+Shift+M on macOS or Ctrl+Shift+M on Linux and Windows, to reopen the discussion.

In a file tab on a computer, right-click the comment-mode button and toggle Show Comments. In Changes, open Display Options and choose Hide Comments or Show Comments. On a phone, open More in the thread header and toggle Comments while viewing Changes. In a file tab, use Comment Mode there to switch between commenting and editing.

On a computer, you can also press Cmd+Option+V on macOS or Ctrl+Alt+V on Linux and Windows while the file or diff tab is focused. Visibility applies to that tab; it does not change your comment-mode preference.

When comments reach the agent

Comments you write are pending until you next submit: they are delivered together with your message, and the agent addresses them in that reply. You can also submit comments on their own, without a message to go with them.

You can reply directly in a pending comment summary. Click inside a teammate’s comment and type to start a reply without returning to the original passage. Typing in your own pending comment edits that draft.

Send one comment chain to a fork

With the cursor in an unsent comment, press Cmd+Shift+Enter on macOS or Ctrl+Shift+Enter on Linux and Windows to send that comment chain to a new fork. If Send With Modifier is off, use Cmd+Enter or Ctrl+Enter instead. This lets you handle that feedback separately from the main conversation. The keymap lists this action as Send Comment to Fork.

How the agent responds

The agent treats comments as feedback aimed at the exact passage it’s attached to: a question to answer, a problem to fix, or a review note to act on. When the agent replies, its answer is linked back to your comment, so you can jump between the annotation and the response. With the cursor in a comment’s summary, press Option+Enter on macOS or Alt+Enter on Linux and Windows to jump to the comment itself.

Click a filename in a comment summary to open the file at the comment’s location. You can still select and copy the quoted excerpt or filename without opening it.

If the commented code has been deleted, Delta opens the file or diff version the comment referred to. Choose View Latest to return to the current review.

Comment replies appear beside the agent’s response while it is still streaming.

When to use comments

Follow-up messages work too. Use a comment when feedback is about a specific place:

• Reviewing a plan the agent proposed, point by point.
• Flagging one line in a code block without quoting it.
• Leaving several independent notes on one long response, each of which gets its own linked answer.

What’s next

• Review & Sync Changes covers reviewing the agent’s edits.
• Collaborate in a Thread covers comment discussions with collaborators in shared threads.