mpm-part-number-manager/references/MPM_SKU_Skill_BuildBrief.md

MPM SKU Skill — Build Brief

Status: Pre-Build / Planning Complete Last Updated: 2026-05-29 Author: Bryan Gilliom (via CoWork session) Pickup: Resume on any CoWork system with Google Drive access to this folder

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Purpose

Build a CoWork skill (mpm-sku) that gives any Claude session — with no prior context — the ability to:

1. CREATE — Given a plain-language description, produce a correctly formatted MPM part number
2. AUDIT — Given one or more existing part numbers, validate them against the schema and surface every structural violation (excluding UniqueID values)

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Architecture Decision: Option A — Reference, Don't Embed

All taxonomy data lives in Google Drive and is read at runtime. Nothing schema-specific is locked inside the skill files.

This is non-negotiable because:

• 10+ CoWork users across multiple machines updating the schema
• The skill would require an update every time taxonomy changes if data were embedded
• All sessions read the same source of truth

What Lives IN the Skill

File	Contents
SKILL.md	Entry points, logic, decision trees, Google Drive file paths
audit-rules.md	Discrete, enumerable validation rules (logic only — no taxonomy data)

What Lives in Google Drive (referenced by path)

File	Path	Status
MPM_SKU_System_Reference.md	Shared drives/DOCUMENTATION/Part - Model Number and Taxonomy Information/	✅ Current — v1.4
MPM_SKU_Sequence_Tracker.md	Same folder	✅ Current
MPM_SKU_Decision_Log.md	Same folder	❌ TO CREATE
MPM_SKU_Undocumented_Subtypes.md	Same folder	❌ TO CREATE

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Files Still Needed Before Skill Build

1. MPM_SKU_Decision_Log.md

A dated log of every taxonomy ruling made. Format: date, decision, rationale, who. This is the audit trail for why the schema is what it is. Seed it with all rulings from this session (see section below).

2. MPM_SKU_Undocumented_Subtypes.md

A structured list of sub-types found in active use across the part number inventory that are NOT yet in the schema. Each entry needs a taxonomy decision before it can be added to the reference. Seed it with the audit findings from 2026-05-29 (see section below).

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Open Decisions (Unresolved — Must Be Settled Before Skill Build)

/YLW vs /YEL — Yellow color code

• /YLW was added to MPM_SKU_System_Reference.md as the canonical code on 2026-05-29
• The existing part number inventory ("Copy of New part number" sheet) uses /YEL throughout
• Decision needed: Is /YLW canonical and the sheet needs correcting? Or should the canonical code be /YEL?
• Until resolved: treat both as a known discrepancy; do not use either as authoritative when auditing

Undocumented MNT- Sub-Types

See MPM_SKU_Undocumented_Subtypes.md (to create). Each needs a formal taxonomy decision before being added to the schema.

Undocumented ACC- Sub-Types

Same — see above.

Solar Panel Variant Descriptors

Items in the inventory use BIF (bifacial), FLX (flexible), RGD (rigid) as ACC-SLR-PNL- variants. These are not in the schema. Need a formal descriptor pattern for solar panel sub-types.

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Decisions Made This Session (2026-05-29)

These are confirmed rulings — seed these into MPM_SKU_Decision_Log.md:

Decision	Detail	Rationale
CLM = Clamp	TypeSuffix CLM under MNT-M- means Clamp, not Column	Confirmed by Bryan during smoke test
/GRY is valid	Added to color code table	Gray hardware is in active use
/YLW is valid	Added to color code table as canonical yellow	Yellow hardware is in active use — but /YEL conflict unresolved
EXD → EX for components	When coding components (PRT-, FAB-, MNT-, etc.) for an EXD-family display, use EX + size + flags (e.g., EX43v) not EXD43k	EXD is a marketing designation; EX43v is the functional descriptor
MPTV-EXD retained	Display product numbers themselves (MPTV- prefix) retain EXD (e.g., MPTV-EXD43k)	EXD is part of the product identity at the display level
PA0510 burned	Do not reuse PA0510 — was assigned to KIT-PRT-SEN-EX43v, then deleted	Burned IDs are never recycled

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Sequence Pool State as of 2026-05-29

Pool	Last Used	Next Available
PA (PRT-, KIT-PRT-)	PA0527	PA0528
FA (FAB-, KIT-FAB-)	FA0511	FA0512
AA (ACC-, KIT-ACC-)	AA0509	AA0510
CA (CBL-, KIT-CBL-)	CA0503	CA0504
MA (MNT-)	Not yet formally assigned under new system	MA0501
SA (PKG-)	Not yet used	SA0501
TA (FST-)	Not yet used	TA0501

Note: MA pool pre-v1.3 assignments exist in the inventory sheet (MA0001–MA0062 range visible) but were assigned before the x0501 starting rule. These are valid legacy numbers. New assignments begin at MA0501 to avoid conflicts.

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Audit Findings — "Copy of New part number" Sheet (2026-05-29)

50-item smoke test surfaced the following issue categories. Full detail in the session transcript.

Issue	Code	Count in 50-item sample	Description
Color suffix before UniqueID	A	17	/Color must always trail the UniqueID. Many items have it reversed.
Undefined color code	B	12	/GRY now valid. /GR, /YEL still invalid per schema.
Undocumented MNT- sub-type	C	9	SPC, BRC, PLT, COV, RL, DIN, ADA in active use
MNT-RL missing M environment segment	D	9	Handrails inconsistently drop the M — MNT-RL- vs MNT-M-RL-
Undocumented ACC- sub-type	E	6+	ADP, CPL, BOX, CLP, CAS, KEY, PRB, DRV, MIC/AMP misrouted
Missing UniqueID	F	3	Solar panels have descriptors in place of an ID — never assigned
Malformed pool ID	G	1	A0022 missing a letter — should be AA0022
ANT sub-type combination format	H	1	GPS-LTE should be combined without hyphen: GPSLTE
Space in part number	I	1	ACC-SLR-PNL- 60W-RGD-24V has a literal space
Structural miscellaneous	J	2	Display model embedded mid-stream; unexplained 311 descriptor

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Undocumented Sub-Types Found in Audit (Seed for MPM_SKU_Undocumented_Subtypes.md)

MNT- Component Sub-Types (under MNT-M-)

Code	Observed Meaning	Example From Sheet	Status
SPC	Spacer	MNT-M-SPC-MA0013/SIL	Needs formal taxonomy entry
BRC	Brace	MNT-M-BRC-MA0014/SIL	Needs formal taxonomy entry
PLT	Plate / Reinforcement Plate	MNT-M-PLT-X-MA0016/BLK	Needs formal taxonomy entry
COV	Cover	MNT-M-COV-MA0019/SIL	Needs formal taxonomy entry
RL	Rail (Handrail)	MNT-M-RL-32mm-2000mm-MA0023/SIL	Needs formal taxonomy entry + environment consistency rule
DIN	DIN Rail	MNT-DIN-SLT-12IN-MA0038	Possibly its own sub-pattern (not MNT-M-)
ADA	ADA-specific mount	MNT-ADA-BRL/BLK-MA0057	Possibly its own sub-pattern

ACC- Sub-Types Not in Schema

Code	Observed Meaning	Example From Sheet	Notes
ADP	Adapter	ACC-ADP-HDMI-RAG-AA0027	Right-angle, signal adapters
CPL	Coupler	ACC-CPL-RJ45-BLK-AA0028	Cable couplers
BOX	Junction Box	ACC-BOX-3WY-BLK-AA0031	Waterproof junction boxes
CLP	Clip / Cable Clamp	ACC-CLP-P-WHT-AA0033	P-clips, cable organizers
CAS	Case / Carrying Case	ACC-CAS-ZIP-GRY-AA0036	Provisioning/tool cases
KEY	Key	ACC-KEY-TRI-SIL-AA0045	Triangle keys, cross keys
PRB	Probe / Tool	ACC-PRB-NDL-WDN-AA0023	LED poke tools, maintenance tools
DRV	Drive	ACC-DRV-FLS-USB-AA0046	USB flash drives (vs ACC-MEM?)
MIC	Microphone (standalone)	ACC-MIC-PNL-SIL-AA0021	Should route through ACC-AUD-MIC per schema
AMP	Amplifier (standalone)	ACC-AMP-160W2-24V-A0022	Should route through ACC-AUD-Amp per schema

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Community Transit Project — Lessons Learned

The EXD43k (TC-Kiosk) spare parts project (2026-05) was the first full exercise of the SKU system at scale.

Key lessons:

• EXD→EX for components is correct and works well. The EX43v functional descriptor cleanly maps components to display family without the marketing suffix.
• COMT/TCK client code pattern is solid. The [CustomerCode]/[Variant] structure before UniqueID disambiguates customer-specific builds without polluting the top-level taxonomy.
• Sequence tracker is essential. Without it, ID conflicts are inevitable across sessions and users.
• PA0510 burned — highlights the need for a formal deletion/burn log in the tracker.
• The CT project deliverable (CommunityTransit_EXD43k_SpareParts_MPM.xlsx) is in the CoWork folder, not referenced by the skill.

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Planned Skill File Structure

plugin: mpm-sku/
├── SKILL.md                    ← Entry points, logic, decision trees, Google Drive file paths
└── audit-rules.md              ← Discrete validation rules (logic, not data)

SKILL.md will reference these Google Drive files at runtime:

• MPM_SKU_System_Reference.md
• MPM_SKU_Sequence_Tracker.md
• MPM_SKU_Decision_Log.md
• MPM_SKU_Undocumented_Subtypes.md

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Nuance Still To Add Before Skill Build

• Resolve /YLW vs /YEL
• Formal taxonomy decisions on all undocumented MNT- sub-types
• Formal taxonomy decisions on all undocumented ACC- sub-types
• Solar panel variant descriptor pattern (BIF, FLX, RGD)
• AUDIT mode issue category definitions (A through J from this session are a good starting point)
• Rule: how the skill handles "unknown sub-type" — prompt for taxonomy decision vs. flag and continue
• Rule: how the skill handles sequence assignment — read-then-increment vs. user confirms before committing
• Rule: batch audit behavior — stop on first error or surface all issues
• MNT-RL environment consistency rule — is MNT-M-RL- correct or is a different sub-pattern needed?
• DRV vs MEM distinction — are USB flash drives ACC-DRV or ACC-MEM-USB?
• HRN (Horn) observed in ACC-ADA-2e-SPK-HRN/BLK-AA0015 — is this a valid ADA variant?
• BRL (Braille) observed in ACC-ADA-1e-BRL/BLK-AA0014 — is this a valid ADA variant or goes through a different field?

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Reference Sheet URLs

Sheet	URL
Revised - Simplified SKU System	https://docs.google.com/spreadsheets/d/1UIUx5BDbcyKHUnRnVtjKpWBOv_IFLJX0K31WHzpxX6Q/edit
Copy of New part number (inventory)	https://docs.google.com/spreadsheets/d/1S2Ftpl19vioHVo6Zl6tX_rX2g8gQXsM34XI2beoVRuY/edit