Catch the receiving problem before the ASN leaves.
Preflight X12 856 and Vendor Shipments API payloads for envelope, hierarchy, SSCC, shipment-reference and schema defects—with the exact location and evidence behind every finding.
3 free checks · no card · no raw document retention by default
HL parent does not exist
segment 18 · HL02
References HL 9 before that parent is defined.
SSCC check digit is invalid
segment 21 · MAN02
GS1 source · exact remediation included
Exact location
Segment, element, or JSON pointer
Evidence first
Source and certainty on every rule
Private by default
Content hash, not raw shipment data
The dispatch gate
Three layers. One actionable report.
Generic syntax validation is only the first layer. Shipment Sentry keeps the conclusion honest when a rule still depends on your account.
- 01 / STRUCTURE
Can it be trusted as a document?
Delimiters, envelopes, control numbers, segment counts, schema and required fields.
- 02 / SHIPMENT
Does the hierarchy describe reality?
HL parentage, purchase orders, shipment type, dates, BOL/PRO/ARN and quantities.
- 03 / LABELS
Will the container identify correctly?
SSCC length, check digit, duplication and message-to-label reconciliation.
Product-led reference library
Every guide ends in a check you can run.
No keyword wallpaper. Indexed pages have a distinct rule, current source trail, accepted/rejected examples, and a relevant tool.
Amazon EDI 856, checked against the shipment—not just the syntax
The EDI 856 is an advance ship notice. For an Amazon Vendor shipment, it communicates shipment identity, timing, transport references, purchase orders, packaging hierarchy, items, quantities, and container identifiers. A useful preflight checks the X12 envelope and HL tree, then applies Amazon-documented shipment rules and flags anything that still depends on the vendor account’s current implementation guide.
Open guide → Error libraryAmazon ASN errors, translated into an exact fix
The fastest way to diagnose an Amazon ASN problem is to separate four layers: X12/JSON parsing, envelope or schema validity, shipment hierarchy and identifiers, then reconciliation with the physical pack and purchase order. Fix the first blocking layer, run the preflight again, and only then investigate account-specific rules.
Open guide → Receiving readinessReceive Accuracy starts before the truck leaves
A preflight can reduce preventable Receive Accuracy problems by checking whether the shipment confirmation is internally valid and reconciling it with purchase orders, pack output, carton or pallet counts, SSCC labels, item quantities, and transportation references. It cannot predict every fulfillment-center observation, so physical receiving evidence and Vendor Central records still matter.
Open guide → Identifier checkerCheck the SSCC before it reaches the carton label and ASN
An SSCC is an 18-digit GS1 identifier for a logistics unit. The final digit is a calculated check digit. Amazon’s public shipment-confirmation guidance says the SSCC must be unique, not reused within 365 days, and represented on both the physical barcode label and shipment confirmation. It also describes adding the GS1 Application Identifier 00 when implementing GS1-128.
Open guide → Hierarchy patternMulti-PO pallet ASN hierarchy without the guesswork
A common multi-PO pallet 856 pattern is SOTPI: Shipment → Order → Tare (pallet) → Pack (carton) → Item. Each HL01 must be unique, every HL02 must reference an earlier parent, and each carton and item must remain connected to the correct purchase order. Confirm the exact profile in the current Vendor Central implementation guide for your account.
Open guide → SP-API implementationVendor Shipments API payloads, preflighted before the 202 response
The Vendor Retail Procurement Shipments API exchanges shipment documents for Amazon vendors. SubmitShipmentConfirmations accepts a request containing one or more shipment confirmation objects. The current public model requires party, identifier, confirmation date, type, and shipped-item data; Amazon’s tutorial adds operational rules such as pre-receipt timing, BOL requirements for FTL/LTL, small-parcel carton confirmation, and SSCC handling.
Open guide → Go-live checklistTest the shipment failures your happy-path 856 never shows
An Amazon Vendor 856 test plan should cover X12 envelope controls, every supported hierarchy and shipment type, required references, item and quantity boundaries, SSCC labels, multi-PO packing, replacements, duplicate/retry behavior, acknowledgements, and reconciliation to warehouse source data. Run accepted and rejected fixtures automatically on every rules or mapping change.
Open guide →The first proof asset
A human-reviewed readiness audit when software alone is not enough.
For a new mapping or expensive recurring issue, get the payload, hierarchy, identifiers, test evidence and risk register reviewed as one implementation pack.
See the $499 audit →Audit output / PDF + call
- Rule-sourced findings with exact locations
- Hierarchy and identifier risk map
- Accepted and rejected test fixtures
- Dispatch-gate checklist for your team
- 30-minute findings walkthrough
Start with the file on your desk