Check the connection and return Max version, open scene path, dirty flag, units, object/selection counts, renderer and listener status.

List the currently selected objects (name, class, layer, position; with detail=True also bbox, transform, parent, material, user properties).

Find scene objects. name_pattern is a MAXScript wildcard ('Wall_*', 'door', case-insensitive); class_name matches classOf (e.g. 'Editable_Poly', 'Box'); layer matches the layer name. detail=True adds bbox, transform, material, user properties.

List all layers with hidden/frozen/current flags and object counts.

Hide (hidden=True) or show (hidden=False) a layer by name. Undoable.

Grab the active viewport to a PNG file and return its path and size. path defaults to %TEMP%/max-mcp/capture_.png. max_size limits the longer edge (0 = keep the viewport resolution).

Execute MAXScript inside Max and return the value of the last expression. (format/print output goes to Max's Listener window; return values instead.) undo=True wraps the code in an undo record.

Execute Python (Max's own 3.11 with pymxs) inside Max. rt (pymxs.runtime) and pymxs are predefined. A single expression returns its value; for multi-line code assign to result. print() output is returned too.

Read the bridge's command history (time, client, tool, summary, duration, ok/error, objects added/removed, selection, undo_state). undo_state is 'on_stack' (max_undo can target it), 'undone' or 'gone'. full=True includes complete args and output.

Undo the bridge's OWN scene changes: either the last steps undo records or everything down to and including history entry to_history_id. Only records labelled 'MCP: #' are undone; if a user's manual step sits in between the call is refused and names it (the user can revert past it from the settings window). Fails when the target has left the undo stack or when AI undo is disabled in the settings window.