Consignment & VMI Stock Tracker

The problem this kills

Consignment and vendor-managed inventory are supposed to make your life easier: the supplier keeps stock physically on your site, you only pay for what you actually consume, and they watch the levels and refill them. In practice the accounting is a nightmare. The stock is sitting in your building, but you do not own it until you use it — and "how much did we use this month" is a question nobody can answer cleanly.

So settlement time turns into an argument. The supplier sends a bill for what they think you consumed. You pull a spreadsheet that says something different. Someone counted the bin last Tuesday and got a third number. Prices changed mid-month and now nobody is sure which price applies to which units. You either overpay to make the dispute go away, or you hold up the supplier's payment and strain the relationship. Meanwhile a fast-moving item quietly runs to zero because the replenishment trigger lived in someone's head.

This is exactly the kind of rules-based, on-site-versus-owned, count-versus-consumed reconciliation that a small internal tool does far better than a spreadsheet — and you do not need to be a developer to build it.

What you'll build

A simple internal web tool for your consignment and VMI program. You import your consignment item agreements (which supplier owns which item, the agreed price, the on-site quantity, and the reorder level) and your consumption records (what got used, when, and how much). The tool keeps consigned stock clearly separate from stock you own, computes the current on-site balance for every item, and works out the amount owed since the last settlement — usage times the right price, even when the price changed mid-period.

When it is time to settle, the tool drafts a consumption settlement per supplier for the period: what was consumed, at what price, and the total owed. A buyer reviews the draft on one screen, reconciles it against a physical count if there's a discrepancy, edits or excludes anything that looks wrong, and clicks Approve. Only then does the tool generate the settlement PO / billing notice to send to the supplier and trigger replenishment for any item that dropped below its reorder level — then export it all to CSV.

What's inside the Implementation Plan

The plan is a single file you paste into an AI coding agent. It opens by interviewing you about your business — which suppliers run consignment or VMI on your site, how your agreements and prices are structured, the exact item and SKU naming you use, how consumption is captured today, your settlement period and approval rules, and your nastiest edge cases — and then tailors the data model, the balance and settlement math, and every later step to your answers. This is a build shaped around your program, not a generic template.

From there it walks the agent through the database schema, the agreement and consumption imports with their duplicate guards, the on-site balance and amount-owed engine (including mid-period price changes and physical-count reconciliation), the buyer's review-and-approve screen, and the export of the settlement PO/notice plus the replenishment list. Every step ends with a ready-to-copy prompt. Because the whole thing runs on CSV in and clean CSV out, you can build and use it this weekend even if you have no direct connection to your ERP or your supplier's portal.

The governance it includes (this is the point)

Settlements move real money to suppliers, so this is built like it matters: login so only your procurement team can use it, row-level security so you only ever see your own organization's data, and a complete audit trail of every import, consumption record, edit, approval, and export — who did what, and when. Nothing is sent to a supplier automatically: a settlement is a draft until a buyer approves it, and that approval is the hard human-in-the-loop gate before any billable PO or notice is issued. Duplicate guards mean the same consumption record can't be counted twice, and the one-settlement-per-supplier-per-period rule means you can't accidentally bill the same usage twice.

Who it's for

Planners and buyers who run consignment or VMI programs and are tired of losing track of usage and fighting disputes at settlement. If you can explain how your stock gets consumed and how you decide what to pay the supplier, you can build this.

You've got this — open the plan, paste the first prompt, and let it interview you about your consignment program.