Ask a side question without derailing the agent
An aside asks the agent a quick question about the conversation. The answer appears in the chat, and the agent never sees it on its next turn.
An aside lets you ask a quick question about the conversation, like "what does that error mean?", without it becoming part of the main thread. The agent answers from everything said so far, and on its next real turn it carries on as if you never asked.
Ask an aside#
Open a session and press Command plus B⌘BCtrl plus BCtrlB. The message box asks you to "Ask an aside", and the send button turns amber.
Type your question and send it.
Read the answer. It appears in the chat with an Aside label.
Press Command plus B⌘BCtrl plus BCtrlB again to go back to normal messages.
Aside mode stays on until you turn it off, so you can ask several side questions in a row.
For a single aside, type your question, then press and hold the send button and choose Send as aside. Your next message goes to the main thread as usual.
Keep asides out of the way#
Once the conversation moves on, earlier asides fold into one line that says how many there were. Click it to open them again.
To fold every aside as soon as it appears, turn on Hide asides by default.
Limit what one aside can cost#
An aside stops when it reaches Aside cost cap (USD), which is $0.50 unless you change it. Anything it wrote before it stopped stays in the chat. To remove the limit, set it to 0.
Which sessions. Asides work in Claude sessions and in sessions on engines that use Claude's tools, such as DeepSeek or Kimi (they use that engine's key).
What the agent sees. The aside runs as a separate, one-time copy of the conversation. The session's own conversation is never changed, so the agent's next turn does not include your side question or its answer.
Exports. Copying or exporting a conversation leaves asides out.