Subthread

Open a quick subthread about any highlighted phrase on claude.ai — ask a side question without derailing the conversation.

Subthread lets you highlight any phrase in a claude.ai conversation and get a quick answer about it in a small popover, without touching the conversation itself. • Explain or Ask on any highlight: select text in a Claude reply, click Explain for a short explanation in context, or Ask to type your own question. • Follow-ups stay in the popover: keep asking in the same side thread while the main conversation stays exactly as it was. • Local history: every subthread is saved per conversation, on your device only, and can be reopened or deleted at any time. Subthread uses your own Anthropic API key — nothing goes through our servers. No account, no analytics, no tracking; the only network destination is api.anthropic.com. Not affiliated with Anthropic.