> ## Documentation Index
> Fetch the complete documentation index at: https://docs.adam.new/llms.txt
> Use this file to discover all available pages before exploring further.

# Diagnose and repair a CAD model

> Find the cause of rebuild failures, missing references, and assembly problems before changing the design.

Start from the first failing feature or missing reference. Later errors may be consequences of that failure, so repairing them individually can create unnecessary changes.

## Capture the failure

Provide the application, document, configuration, recent change, and error text. Include a screenshot if it shows the feature tree or problem area. Keep a recoverable copy or revision of the model.

```text title="Diagnose a failed rebuild" wrap theme={null}
Inspect the rebuild errors in [document] after the [recent change]. Identify the earliest failing feature and its missing or invalid inputs. Explain which later failures depend on it. Propose a repair that preserves the mounting interfaces and design intent, and identify any reference that cannot be matched unambiguously.
```

## Apply a focused repair

**1. Confirm the cause**

Check whether the problem is a missing source, changed topology, conflicting constraint, or invalid geometry.

**2. Repair the smallest affected area**

Restore or replace the intended reference, correct the parameter, or revise the feature. Rebuild after the change.

**3. Inspect downstream effects**

Check dependent features, dimensions, assembly relationships, and drawings. A cleared error icon is only one part of the check.

```text title="Verify a repaired reference" wrap theme={null}
After repairing the sketch reference, rebuild the complete model. Check the original hole locations, overall dimensions, and affected assembly relationships. Report any remaining suppressed or failed features, then update the working copy and provide a change summary.
```

## Common recovery paths

| Symptom | Start by checking |
| - | - |
| Missing external reference | Source availability, file path, permissions, and revision |
| Failed fillet or shell | Changed neighboring geometry, radius or thickness, and the first failing feature |
| Overconstrained sketch | Conflicting dimensions, constraints, and intended degrees of freedom |
| Mate conflict | Component positions, replaced geometry, and the intended assembly relationship |
| Broken drawing reference | Source document, configuration, part identity, and drawing revision |

If an operation was interrupted, ask Adam to inspect the current state before repeating it. For connectivity problems, use [Troubleshooting](https://docs.adam.new/resources/troubleshooting.md). For drawing checks after a repair, see [Drawing review](https://docs.adam.new/cad/drawing-review.md).


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