Arena

The real-time collaboration layer with voice, video, shared editing, and automatic decision extraction in a unified workspace.

Arena is the real-time collaboration layer. It merges live conversation, shared code editing, and automated decision extraction into a unified workspace where meetings produce artifacts, not just notes.

Core Components

Arena brings together three surfaces in one workspace:

Voice and Video

Built-in voice and video powered by LiveKit:

  • HD video with filmstrip and gallery view modes
  • Screen sharing optimized for text clarity (VP9 with SVC encoding)
  • Noise cancellation with echo cancellation, noise suppression, and auto gain
  • Picture-in-Picture to pop video out to a floating window
  • Automatic transcription with speaker attribution
  • Recording (host-controlled, when enabled for the team)

Everyone in a Space shares one room. Switching between projects doesn't disconnect you from the call.

Shared Editor

Real-time collaborative code editing powered by CodeMirror and Automerge CRDT:

  • Conflict-free editing so multiple people can edit the same file simultaneously
  • Remote cursors to see where other participants are typing
  • Syntax highlighting for 50+ languages
  • Markdown mode with live preview, format bar, and image embedding
  • Auto-save that syncs all edits automatically, no save button needed
  • Provenance tracking where every change is attributed to the person or AI that made it

Decision Topics

AI monitors conversations and workspace activity to detect high-level meeting topics in real time. Every 90 seconds, the system analyzes new transcript segments, detects topic shifts, and writes structured meeting notes with labeled items: Intent, Decision, Implementation, Idea, and Open Question.

A coverage checker compares detected topics against your Meeting Context files to flag which topics contain new information. You can apply topics to send them to the AI agent for context file updates, or dismiss them.

Topics appear in the Decision Topics section of the sidebar with a badge count for topics with new information.

Session Lifecycle

Creating a Session

Sessions are created automatically when you open a Space workspace. The system either:

  • Reuses an active session if one already exists
  • Creates a new session for the Space

Note

New session creation is blocked during maintenance windows.

During the Session

While a session is active:

  • Transcription captures all spoken content with speaker attribution
  • Editor changes are tracked with per-character attribution
  • AI agent can be started to write code and build prototypes
  • Decision Topics appear as the AI detects meeting subjects
  • Chat messages are available for text-based discussion

After the Session

When the session ends:

  • Full transcripts are saved with timestamps and speaker names
  • Decisions are finalized with links to source context
  • Code changes are committed to the CRDT
  • Content syncs to Repo for versioning
  • Meeting notes markdown file is preserved

Integration with Capture

Arena feeds into the same system as Capture. Decisions from live sessions use identical formats, search indexes, and provenance models as decisions captured from CLI sessions. Everything is unified in the journal.

Use Cases

Meeting TypeWhat Stoa Captures
Architecture reviewsDecisions with rationale, linked to code changes
Pair programmingPer-character attribution showing who wrote what
Engineering kickoffsScope decisions, technical approach, ownership
Design handoffsRequirements translated into code with provenance
Incident responseTimeline of decisions and fixes, fully documented
RetrospectivesStructured outcomes instead of ephemeral notes

Access Control

Sessions support multiple access levels:

  • Team members get full access to all features
  • Admins/Owners can manage settings, start recording, and control the agent
  • Guests can join calls, view files, and chat, but cannot start the agent or access team settings

See Guest Access for details on inviting external collaborators.

What's Next