Summarizer
Summarizes the unread messages in a chat when you open it
About this app
A sidebar widget that reads the messages you have not caught up on and posts a short AI-generated summary, so you can rejoin a busy room without scrolling back through everything.
When opened, it looks at the room timeline up to your read marker
(m.fully_read), collects the unread m.room.message events, resolves the
senders from m.room.member, and asks an LLM to condense them. The summary is
shown inside the widget — nothing is written back to the room.
Built by Beeper as a demo for their widget SDK. It runs against Beeper's fork
of the Matrix Widget API (@beeper/matrix-widget-api) and needs a companion
backend that holds an Anthropic API key: the widget's own Next.js API route
(/api/completion) proxies the request to the Claude API so the key never
reaches the browser. Because of that server route — and because the repo
carries no license — it is listed here only, pointing at Beeper's own
deployment, and is not built or hosted by Marcade.
Add to a room
Paste this into any room you may configure — Element and most clients understand /addwidget:
/addwidget https://summarizer.beeper.vercel.appMarcade does not build or host this app — the URL is the deployment run by Beeper, and it can change under you at any time.
Name and icon in Element
/addwidget can carry only the URL: Element lists the app as “Custom” without an icon. Add the Marcade Store once per room and it gives every Marcade app pasted in there its name and icon, and tells you when an update is out.
/addwidget https://marcade.store/apps/de.minagawa.marcade-store/0.1.4/Permissions
Capabilities this widget may request. The Marcade Player asks for your consent before granting any of them.
- Read room state events of type “m.room.member”
org.matrix.msc2762.receive.state_event:m.room.member - Read messages in the room
org.matrix.msc2762.receive.event:m.room.message
Backend services
This widget requires a companion service to work:
summarizer-next
Information
- Section
- Unverified — Listed only. Marcade builds and hosts nothing; the link goes to the author’s own deployment.
- License
- NOASSERTION
- Author
- Beeper
- Source code
- https://github.com/beeper/widget-summarizer
- Issue tracker
- https://github.com/beeper/widget-summarizer/issues
- Encrypted rooms
- Not declared
- Widget ID
com.beeper.summarizer