Shape Builder: double-clicking the tool opens Shape Builder Tool Options

Double-clicking the Shape Builder tool reported that the tool has no
options. The reference app opens Shape Builder Tool Options there.

The dialog sets Consider Open Filled Paths as Closed, Pick Color From
(Artwork or Color Swatches), Cursor Swatch Preview, Selection (Freeform
or Straight Line) and Highlight Fill. The defaults keep today's
behavior. With Consider Open Filled Paths as Closed off, a filled open
path cuts regions as an unfilled one does. With Color Swatches, a merge
fills the new shape with the current fill, and the Left and Right arrow
keys step the current fill through the document's color swatches.
Cursor Swatch Preview shows the current fill and the swatches before
and after it above the pointer. With Straight Line, a drag merges what
the line from its first point to its last crosses. With Highlight Fill
off, merge mode shades no regions.

The options persist like other tools' options. shapeBuilder.merge
takes openFilledAsClosed and pickColorFrom, and shapeBuilder.regions
takes openFilledAsClosed. Gap Detection, "In Merge Mode, Clicking
Stroke Splits the Path" and Highlight Stroke When Editable are not part
of this change.

Docs: docs/mcp.md, docs/target-app-parity.md.

docs/mcp.md

@@ -4196,7 +4196,7 @@ active tool, `tool` names another one, and `{}` just reads them; the result is t
 tool keeps last across tool switches (and documents) and are saved with the preferences (`toolSettings` in
 `prefs.get`'s full object), as the reference app keeps them: the Liquify tools' brush and tool options, Mirror & Cut's
 axis and side, Puppet Warp's mesh, the Symbolism brush, the line, grid, pencil, brush and eraser tools' options,
-polygon sides and star points, and the Flare Tool Options. The Liquify tools share one set of Global Brush Dimensions (width, height, angle,
+polygon sides and star points, the Flare Tool Options and the Shape Builder Tool Options. The Liquify tools share one set of Global Brush Dimensions (width, height, angle,
 intensity), and the Symbolism tools one brush. Interaction state (pins, a reference point) starts afresh.
 
 ```json
@@ -4224,6 +4224,21 @@ default name, "Artboard N" for the Nth artboard.
 {"name":"run_command","arguments":{"command":"tool.setOption","params":{"tool":"flare","values":{"rays":24,"ringsOn":false}}}}
 ```
 
+The Shape Builder tool's options are its Shape Builder Tool Options (dialog `shapeBuilderOptions`):
+`openFilledAsClosed` (on: a filled open path bounds a region as if an invisible edge closed it; off: it cuts regions
+as an unfilled path does), `pickColorFrom` (`artwork`, the default: a merged shape takes the fill of the front-most
+object over the first region the drag touches that an object covers, and the current fill when only lines enclose
+every region touched; `swatches`: the current fill, and the Left and Right arrow keys step the current fill through the
+document's color swatches), `cursorSwatchPreview` (off; with `swatches`, chips above the pointer show the current fill
+and the swatches before and after it), `selection` (`freeform`, the default, or `straightLine`: a drag touches what
+the line from its first point to the pointer crosses) and `highlightFill` (on by default; when it is off, merge mode
+shades no regions). The tool sends `openFilledAsClosed` and `pickColorFrom` with `shapeBuilder.merge`, which takes
+both as params, and `shapeBuilder.regions` takes `openFilledAsClosed`.
+
+```json
+{"name":"run_command","arguments":{"command":"tool.setOption","params":{"tool":"shapeBuilder","values":{"selection":"straightLine","pickColorFrom":"swatches"}}}}
+```
+
 ## Perspective grid
 
 The grid is document data (`perspective.grid.set` edits the model directly). `perspective.grid.get` reads it:

docs/target-app-parity.md

@@ -590,6 +590,7 @@ Moved from the ROADMAP's "Shipped so far" on 2026-10-10. Update it when a featur
   - **Tool double-clicks:** double-clicking a tool's button opens its options: Hand fits the artboard in the window, Zoom shows 100 %, Rotate, Scale, Reflect and Shear open their Object › Transform dialogs, the Selection, Direct Selection and Group Selection tools the Move dialog (Enter opens these seven tools' dialogs too; Move opens on the offset of the last drag or Move and with the checkboxes it was last confirmed with, so Enter, Enter repeats a move or a copy at the same spacing, as [an Adobe Community thread](https://community.adobe.com/questions-652/move-tool-771221) describes), Gradient, Eyedropper, Blend and the Liquify tools their panels or options, the Pencil, Paintbrush, Smooth, Blob Brush and Eraser tools their Tool Options (Fidelity, fill, Keep selected, the tolerances, the brush size), and (#812) the Flare tool its Flare Tool Options, the Artboard tool the active artboard's Artboard Options, the graph tools Graph Type for the selected graph, the Symbolism tools the Symbolism Tools Options (Diameter, Intensity, Symbol Set Density) and the Magic Wand tool its panel.
     In the Pencil and Paintbrush Tool Options, Edit selected paths within 0 px turns editing off, so a stroke that starts exactly on an end of a selected open path draws a new path; Close paths when ends are within 0 px turns closing off, so a stroke that ends exactly where it started stays open.
     Keep selected in the Pencil and Paintbrush Tool Options is on by default; while it is off, the path a stroke draws or continues is not selected afterwards and the rest of the selection stays as it was (`path.freehand` `keepSelected`).
+    Double-clicking the Shape Builder tool opens Shape Builder Tool Options ([Shape Builder tool options](https://web.archive.org/web/20260105172244/https://helpx.adobe.com/illustrator/using/building-new-shapes-using-shape.html)): with Consider Open Filled Paths as Closed off, a filled open path cuts regions as an unfilled one does; Pick Color From Color Swatches fills merged shapes with the current fill, the Left and Right arrow keys step it through the document's color swatches, and Cursor Swatch Preview shows the current fill and the swatches before and after it above the pointer; Selection Straight Line merges what the line from a drag's first point to its last crosses ([Setting Illustrator's Shape Builder Options](https://web.archive.org/web/20260615204453/https://creativepro.com/setting-illustrators-shape-builder-options/)); with Highlight Fill off, merge mode shades no regions (`shapeBuilder.merge` `openFilledAsClosed` and `pickColorFrom`). Gap Detection, "In Merge Mode, Clicking Stroke Splits the Path" and Highlight Stroke When Editable are not built.
     The Blob Brush Tool Options have Keep selected and Merge only with selection, both off by default: while Keep selected is off, the blob a stroke draws or merges into is not selected afterwards, and while Merge only with selection is on, a stroke merges only with selected blobs of its color that it touches (`path.blob` `keepSelected` and `mergeOnlySelection`).
 - **Ruler guides as layer objects:** a guide goes on the current layer, shows, hides, locks and is deleted with it, is listed in the Layers panel (its row selects it) and moves to another layer (`guide.setLayer`, or its row dragged onto that layer's rows); guides on a hidden or locked layer can't be selected, moved or deleted, Duplicate copies a layer's guides and Merge Selected and Flatten Artwork keep them on the merged layer; guides from files saved before guides had layers go on the top visible, unlocked layer when the document opens. Not done: guides stacked among the art of their layer (they are listed above it), a guide row's own eye and lock. Lock Guides also locks the objects made into guides: they can't be selected, moved or deleted (#1543); they are drawn in the guide colour and style of Preferences, and a dragged selection snaps to ruler guides with Smart Guides on (#1583, fixes #1534). The Transform panel shows a selected ruler guide's X or Y, and typing a value moves it (#1659, part of #1597). This is not established by the documentation we could find: the public help pages on guides, rulers and the Transform, Control and Properties panels (read again on 2026-10-14) describe selecting and dragging unlocked guides and the panels' X and Y for a selection, not a guide's position in a panel, and the one public statement of it is a user's [community answer](https://community.adobe.com/questions-652/adding-a-new-custom-guide-785586), which is not documentation. It is kept as a convenience pending the owner's decision, with no parity claim and nothing counted towards a score.
 - **Releasing ruler guides:** View › Guides › Release Guides turns the selected ruler guides into paths with no fill or stroke. An artboard guide becomes a line across its artboard, and a canvas guide becomes a line across the artboards (`view.guides.release {index?, ids?}`). A Cmd/Ctrl+Shift double-click with the Selection, Direct Selection or Group Selection tool releases the ruler guide or guide path under the pointer.