Esl Price Sync

---
name: esl-price-sync
description: Synchronizes retail prices between ERP/POS systems and Electronic Shelf Labels (SES-imagotag, ZKONG, Pricer, Hanshow, SOLUM) with delta watermarking, idempotency, and battery modeling. Trigger phrases
category: Document Processing
source: antigravity
tags: [python, api, claude, ai, workflow, template, design, document, rag, cro]
url: https://github.com/sickn33/antigravity-awesome-skills/tree/main/skills/esl-price-sync
---


# ESL Price Sync: Deterministic Retail Shelf-Edge Pricing Architecture

Ensure strict real-time parity between ERP/POS price masters and Electronic Shelf Label (ESL) fleets (SES-imagotag, ZKONG, Pricer, Hanshow, SOLUM) via bounded delta streams, monotonic idempotency tokens, and Sub-GHz RF battery preservation models.

## When to Use This Skill

Activate this skill when:
- Designing, implementing, or auditing integration pipelines between enterprise retail masters (SAP, Oracle Retail, Dynamics 365, Lightspeed) and ESL server platforms.
- The user asks: "How do I sync price updates to ESL tags without draining batteries?", "Debug ghost pricing where POS doesn't match the shelf tag", "Design an idempotent delta feed for ZKONG or SES-imagotag", or "Schedule promotional pricing with automatic rollback".
- Reconciling price discrepancy logs between central ERP databases, ESL middleware, and wireless base station ACK telemetry.
- Calculating battery life depletion curves for e-paper tags running on CR2450 coin cells under varying refresh frequencies.

Do NOT use this skill when:
- Managing e-commerce web store frontends or dynamic pricing algorithms (this skill governs faithful delivery of decided prices to physical tags).
- Troubleshooting individual dead hardware tags before gateway RF coverage and RSSI signal propagation have been verified.
- Performing live write operations on production store fleets without a preceding read-only audit verification pass.

## Core Mental Models & Non-Negotiable Rules

1. **The 5-Layer ESL Architecture Pipeline**:
   - Every price synchronization event traverses five distinct operational tiers:
     $$\mathbf{Price\ Master\ (ERP/POS)} \xrightarrow{\text{Extract}} \mathbf{Transform\ Middleware} \xrightarrow{\text{API/Message}} \mathbf{ESL\ Server} \xrightarrow{\text{Sub-GHz/2.4GHz}} \mathbf{Base\ Station\ (AP)} \xrightarrow{\text{RF\ Packet}} \mathbf{Physical\ Tag}$$
   - **Traceability Invariant**: Every price payload MUST carry a deterministic `trace_id` recording timestamps and status codes across all five layers. A "200 OK" from the ESL central server API is NEVER treated as proof that the physical shelf display has updated.

2. **Strict Delta Discipline & Cryptographic Watermarking**:
   - Pushing a full 50,000-SKU store catalog on a scheduled cron is strictly forbidden.
   - Updates MUST be generated by calculating a cryptographic row hash:
     $$\text{RowHash} = \text{SHA256}(\text{SKU} + \text{BasePrice} + \text{PromoPrice} + \text{Currency} + \text{UnitOfMeasure} + \text{Barcode} + \text{TemplateID})$$
   - Only records where $\text{RowHash}_{new} \neq \text{RowHash}_{pushed}$ are queued for transmission.
   - Full pushes are strictly restricted to initial store commissioning and disaster recovery restores.

3. **Monotonic Idempotency & Out-of-Order Packet Defense**:
   - High-volume retail message brokers inevitably deliver packets out of order during network re-balancing.
   - Every transmission packet MUST include an `idempotency_key` and a monotonically increasing `version_timestamp` (ISO 8601 UTC).
   - If an incoming price payload has $\text{version\_timestamp} \le \text{last\_applied\_version}$, the ESL middleware MUST discard the payload to eliminate race condition reversions.

4. **RF Gateway Rate-Limiting & Battery Longevity Budget**:
   - Each physical e-paper display refresh costs between $12\ \mu\text{Ah}$ and $25\ \mu\text{Ah}$.
   - A dual-CR2450 battery pack provides $1,200\text{ mAh}$ nominal capacity ($960\text{ mAh}$ usable considering passivation and low-temperature shelf environments).
   - **The 3-Update Daily Rule**: Limiting tag updates to $\le 3$ refreshes per day guarantees a $5.5\text{--}7\text{ year}$ operational lifespan.
   - **Base Station Queue Throttling**: Gateways operate over shared Sub-GHz (868/915 MHz) or proprietary 2.4 GHz RF channels. Batch transmissions must not exceed 150 tag updates per gateway per minute to prevent RF collision retries from draining batteries.

5. **Read-Only Audit Mode by Default**:
   - Diagnostic and reconciliation tasks MUST execute in read-only audit mode.
   - Output discrepancy reports containing SKU, ERP Price, Gateway ACK Price, and Divergence Layer.
   - State-changing write updates require explicit operator consent.

## Named Sins & Anti-Patterns (Что категорически ЗАПРЕЩЕНО)

| Anti-Pattern | Manifestation in Code/Workflow | Mandatory Production Counter-Rule |
| :--- | :--- | :--- |
| **Scheduled Full Catalog Floods** | Blasting 60,000 tags every night at midnight. | Stream strict deltas using SHA256 content watermarks. |
| **Ghost Price Blindness** | Assuming API `200 OK` means the customer sees the new price. | Track gateway ACK packet receipts (`status: ACK_CONFIRMED`). |
| **Non-Idempotent Retries** | Retrying failed HTTP calls without idempotency keys. | Attach `UUIDv5(sku, store_id, price_timestamp)` to all mutations. |
| **Timezone Ambiguity** | Pushing promo prices without UTC/local time