CAIBI project benchmark: MX MIDI Guitar
Prompt version 1.0

Help me build MX MIDI Guitar using the existing creator project at https://learn.adafruit.com/mx-midi-guitar. This is a CAIBI benchmark adaptation of the project build brief, not a claim about how the creator used AI.

Project context:
- A guitar-shaped USB MIDI controller with key switches, selectors and motion input. It controls a host instrument; it is not a standalone sound generator.
- Build context: Grand Central M4 Express, LIS3DH accelerometer and twelve MX switches; Two 10k panel potentiometers, mini potentiometer, two lever microswitches, eight-way selector and two toggles; USB extension, proto board, wiring, fasteners and the source whammy hardware; Printed body, neck and control parts in the exact quantities listed in the creator files.
- Fabrication scope: The source supplies STL and editable STEP files, print quantities and support-free FDM guidance. It describes a roughly 250 × 210 × 200 mm printer envelope; check the longest neck part against your machine. Use the source quantities rather than scaling the guitar to fit.
- AI role: AI can reconcile the BOM, explain the CircuitPython mapping and help troubleshoot MIDI messages. You must check wiring, mechanical travel, solder joints and every input.
- Known limitation: Source-based desk assessment only. No CAIBI physical build, current substitution approval or complete delivered UK/US cost.

Read the source first. Use its published design, files, dimensions and parts as the baseline; do not redesign it unless a missing detail requires a clearly labelled proposal. If you cannot access a source or verify a revision, say so.

Provide one practical build package:
1. Design and files: explain the source design, link the original editable files, and identify missing files or modifications.
2. Parts and fabrication: give quantities, exact variants and compatibility, plus a cutting or printing list where applicable. Preserve source dimensions; flag anything unconfirmed.
3. UK and US purchasing: direct product links, checked dates, stock, pack sizes, taxes, delivery and regional costs. Mark unverifiable details as unknown; do not invent links, prices or availability.
4. Assembly: an ordered guide covering fabrication, fitting, wiring or software as applicable, setup, checks and troubleshooting.
5. Cost and time: separate parts, fabrication, delivery, hands-on time and machine time, with assumptions and exclusions.
6. Function and ease: a test plan for the project's stated purpose, likely difficulties, required skills and any corrections or limitations.

Keep source facts, your proposals and items needing physical verification distinct. An estimate is not a measured build result. Do not claim to have built or tested hardware. Include failed attempts and omissions. If a section does not apply, say why.

Use the source as accessed during this run and record its revision or access date. The prompt is fixed; the linked source can change.