# Repository channels

Chopin keeps channel metadata in the selected storage adapter and uses GitHub as
the current authorization source. An identity must first pass the instance's
optional user or organization admission policy. Browser routes, WebSockets, and
the hosted Planner then require a repository to appear in the intersection of
the authenticated user's access and a personal or organization GitHub App
installation. The installation must include that repository. Merely being
public is not enough to expose its Chopin channels through those surfaces.

GitHub read access may list and open channels. Push or admin access may create a
channel and mutate its plan, chat and decisions. The HTTP API and WebSocket
upgrade both recheck those permissions; open sockets revalidate their
session and repository access periodically.

Local MCP checks the caller-supplied bearer token's repository permissions
directly and does not require the Chopin App installation. A channel created
through MCP remains unavailable to the browser, WebSockets, and hosted Planner
until the installation includes its repository.

```text
GET  /api/repositories/:owner/:repository/channels
POST /api/repositories/:owner/:repository/channels
GET  /api/channels/:channelId
POST /api/channels/:channelId/agent/reset
```

Channel IDs are random lowercase UUIDs. The stored repository node ID is the
authority; owner and name are retained to resolve the repository and are never
trusted as substitutes for that ID.

The web client uses ordinary document navigation:

```text
/                                      repository list
/repositories/:owner/:repository      channel list and creation
/channels/:channelId                   chat, plan and decisions workspace
```

Channels persist their canonical MDX, complete Yjs checkpoint,
post-checkpoint update journal, transcript, authoritative open/answered/cancelled
question records and draft CRDTs, comment records, decisions, and question or
comment relationships through `StorageAdapter.collaboration`. Checkpointing
deletes journal updates through the checkpoint sequence; it is a recovery tail,
not permanent document history. A client update is acknowledged only after its
fenced durable commit.

Agent turns use the first invoking editor's process-local GitHub App session and
repository-scoped GitHub tools. The isolation and ownership model is described
in [Copilot agent](hosted-agent.md).