capwitf/mechanical-cad-skills/cad-toolchain-preflight

CAD Toolchain Preflight

Core Rule

Do not trust a CAD toolchain because it is popular, installed, or produced a sample image. Trust it only after it passes a task-appropriate local preflight.

earthtojake/text-to-cad is appropriate for parameterized mechanical geometry with a STEP-first artifact path. It is not an illustration tracing tool: do not select it for portraits, posters, logos, photographs, or freehand artwork that only need editable 2D line art. Route those requests to cad-illustration-vectorization.

External Skill Intake

Before installing, localizing, or relying on an external GitHub/registry CAD skill, MCP server, or automation package, use cad-external-skill-intake first.

Keep the phases separate:

Only continue from external intake to local preflight when the candidate is Green or Yellow with explicit risk reporting. Red candidates require a different tool path or user approval to continue despite risk.

Maturity Check

Before installing or relying on an external CAD skill or MCP server, check:

• install count or adoption,
• GitHub stars/forks/issues,
• latest commit or release date,
• supported CAD versions and operating systems,
• whether the project says alpha, experimental, untested, demo, or prototype,
• whether the task needs native SolidWorks files or neutral exports are enough.

Treat maturity as a risk signal, not as proof of engineering correctness.

Local Preflight

Run the smallest possible local proof before real work:

If the preflight fails, switch tools or report the blocker. Do not continue as if the path is verified.

Tool Risk Levels

• Green: local preflight passed and output format matches the task.
• Yellow: tool works partly, but native format/export/render needs manual verification.
• Red: install fails, tool cannot launch, output is blank/stale, or project is too experimental for the requested deliverable.

Use yellow or red tools only with explicit risk reporting and a fallback.

External Skill Notes

Useful candidates to verify at task time:

• earthtojake/text-to-cad for general parametric CAD and STEP/DXF-oriented work.
• wzyn20051216/solidworks-automation-skill for Windows SolidWorks automation, after COM/API preflight.
• FreeCAD scripting or FreeCAD MCP options when FreeCAD is acceptable.

Do not install external skills globally unless the user allows it or the current task clearly needs it.

Handoff

After preflight:

• Return the selected tool path and risk level.
• Record exact commands or checks run.
• Use cad-final-verification for final deliverable checks.
• Use cad-solidworks-native-preflight before any native .sldprt, .sldasm, or .slddrw readiness claim.
• Use cad-reference-match if visual/reference similarity matters.

Common Mistakes

• Treating a GitHub star count as a working local install.
• Using a SolidWorks MCP server before confirming SolidWorks can launch and rebuild.
• Trusting a neutral STEP export as evidence that native SolidWorks files are correct.
• Continuing after a blank render because the command exited with code 0.