How CADABRA works

What is sent with each prompt

Your CAD file is never uploaded. What goes with a prompt is a bounded reading of the open document, assembled fresh each turn.

The live situation

Whether a document is open. Its name, type, path, active configuration, configuration count and units. Whether you are in a sketch, the feature count and any rollback state. The current selection. An assembly summary. And up to 12 features currently in error or warning.

The digest, for parts and assemblies

Up to 60 features, up to 16 custom properties, and one geometry block: bounding box, mass, volume, material and body count. The caps are hard. On a 300-feature part the model sees 60 of them plus whatever retrieval adds, which is why naming the feature you mean beats saying "the last one".

Retrieval

When a document opens, CADABRA indexes it: metadata plus up to 400 feature-tree nodes, embedded and stored, with the top 6 matches for your question appended to the prompt.

Indexing is skipped for assemblies, skipped for drawings, and skipped for parts over 1,500 features, because walking those trees on open would freeze the SOLIDWORKS UI thread. Those documents are read on demand instead. It is off entirely on accounts with zero retention or encryption at rest, where the service refuses to store anything to index. See data handling.

Changes are native SOLIDWORKS operations

CADABRA drives native operations through the SOLIDWORKS COM API: sketching, features, holes and fasteners, patterns and mirrors, feature-tree edits, reference geometry, assembly and mate edits, properties, configurations and export. An extrude it creates is the same extrude you would have created, in the same tree, with its sketch and dimensions intact.

When no native operation matches the request, and only then, the agent falls back to generated VBA. Read-only modes never receive that tool.

There is no import step and no foreign body, so rollback, reordering and suppression behave normally, PDM revisioning is unaffected, and a colleague without CADABRA installed can open and edit the file.

What happens after each operation

CADABRA scans the rebuild errors in the document before the edit, performs the operation, rebuilds, and scans again. The comparison is what lets it separate an error your edit caused from one that was already in the file, and it reports them differently.

If a single operation fails after it changed a value, the value it captured is restored and re-read to confirm the restore. When that restore itself fails the message says so, names what could not be put back, and tells you to inspect the value before continuing.

A number that cannot produce valid geometry is refused before the model is touched, rather than producing a broken feature you find later.

What revert really does

CADABRA does not group a run into a single SOLIDWORKS undo record. Revert is a feature-tree diff, matched by feature id so a rename in between does not confuse it.

Reverting the last step deletes the last feature in the tree, and only in a part, because the last node in an assembly can be a mate or a component rather than the step you asked for. Reverting the build deletes every feature the current run created: the tree is recorded at the first change of the run, and that record is dropped when the next prompt starts. A revert has to happen in the run that made the change. After that, delete the feature by name.

• Features the run created are deleted, and the message names them.
• A feature it could not delete is named and left, with an instruction to remove it yourself.
• An in-place change that added no feature, such as a dimension value, a material or a property, is reported as not undone: "Re-apply the original values manually if they must be restored."
• A feature the run deleted is gone. Deletion is not reversed by revert.

Ordinary SOLIDWORKS undo still exists, but it is not what CADABRA uses, and after a run the rebuilds and selection changes in between make it unreliable. There is no file checkpoint and no save-and-reopen safety net. Save before a long run.

Drawings Mode is the one exception. Its edit undo uses the native SOLIDWORKS undo record and reliably reverses a delete. A move has to be reverted by moving back.

What the checks do not cover

CADABRA can tell that an operation did nothing when it claimed to do something, and it can tell that the rebuild is clean. It cannot tell you that the geometry it produced is the geometry you wanted. Size and position are not checked against your intent, because your intent is not in the file.

Review the result.

Limits

• It is not a CAD system. It runs inside SOLIDWORKS and cannot run without it.
• It is not offline. The reasoning runs in the CADABRA service, so every prompt needs the network.
• There is no manufacturability score, no cost model and no price data. What exists is the assistant reasoning in prose over the open document plus live web search.
• It does not replace engineering judgment, and nothing it produces is checked for fitness by anything other than you.