Inspect a workspace through MCP

@libtmux/workspace 0.1.0-alpha.12 · Source

Inspect the session you loaded with the TypeScript workspace CLI by pointing its MCP server at the same tmux socket. The loaded windows and panes are ordinary tmux objects; discovery returns their existing IDs.

This guide uses development workspace-cli source. Continue the installation walkthrough through its detached load, keeping that shell and WORKSPACE_TMP available. Leave the workspace-guide session running. Build both executables from the same native repository checkout; released package instructions may describe different MCP contracts.

Build the MCP server¶

Run from the native repository root with the installation walkthrough’s toolchain and dependencies.

$ bun run --cwd packages/mcp build

The installation walkthrough has already installed the frozen dependencies and built the local core package. Keep the MCP output chunks, workspace packages and installed dependencies available to Node.

Select the same socket¶

Configure an MCP client to launch the following command with the shown environment. The client owns the process’s standard input and output for JSON-RPC messages.

$ LIBTMUX_TOOLSETS=inspect \
    LIBTMUX_SOCKET_PATH="$WORKSPACE_TMP/tmux.sock" \
    node packages/mcp/dist/server.js

In a client’s configuration file, use absolute executable or script paths and expand WORKSPACE_TMP to its actual value. Configuration files do not perform shell variable expansion. Retain the environment used to build and run the native executable.

For a workspace loaded with -L NAME, set LIBTMUX_SOCKET=NAME instead of LIBTMUX_SOCKET_PATH. Do not set both. If the CLI selected a binary through TMUX_BIN, give that same path to MCP through LIBTMUX_TMUX_BIN.

Inspect and wait¶

1. Discover tools with tools/list and read the rtmux://capabilities resource. Confirm that its resolved endpoint matches the loaded socket.
2. Call list_sessions, then list_windows with session: "workspace-guide", and list_panes. Retain the returned session, window and pane IDs.
3. Select one returned pane ID for capture or a bounded text wait. Use the argument names below; discover the full schema before adding options.

Set "timeoutMs" to 10000 for a ten-second wait. A pending wait permits other inspection calls on the same connection. To check that behavior, start a wait for text absent from the pane, then request list_panes before its deadline. Client cancellation uses notifications/cancelled with the outstanding request ID; the connection remains usable for inspection.

Capture omits trailing empty rows. Use snapshot_pane for structured pane state and capture_since for incremental observation; their budgets and cursor fields are described in the discovered schemas.

If discovery does not show workspace-guide, compare the resolved socket in capabilities with the CLI’s -S path. A different socket selects a different daemon even when session names match.

Close the connection¶

Close the MCP connection’s standard input to stop the server and release pending work. This separately loaded workspace remains running. When you finish the walkthrough, remove only its session on the same socket:

$ tmux \
    -S "$WORKSPACE_TMP/tmux.sock" \
    kill-session \
    -t '=workspace-guide'

The configuration remains in the temporary directory until you remove it.

See the verified native workspace workflow and development MCP reference for this source contract. The site’s released MCP pages retain their version-pinned contracts.