What does an ERP integration need to cover?
“Connects to ERP” is an incomplete requirement. A planning tool may read demand history, read inventory snapshots, write an approved forecast, or create a proposed purchasing action. These are different interfaces with different permissions and consequences.
List each flow separately. Keep exploratory scenarios distinct from approved operational outputs. A planner should be able to test a demand increase without accidentally changing a purchase order.
Define the interface contract
| Decision | Questions to resolve |
|---|---|
| Direction | Read-only import, approved export, or both? |
| Ownership | Which system owns item IDs, units, lead times, and order status? |
| Timing | Scheduled batch, manual refresh, or event-driven update? |
| Approval | Which state permits a write to the receiving system? |
| Validation | Which records must be rejected rather than partially accepted? |
| Identity | What stable key identifies an item, location, and transaction? |
| Recovery | How are failures surfaced and safely retried? |
| Reconciliation | How do both sides prove the same quantity and status? |
Record the supported interface and version in the project scope. A generic connector logo is not confirmation that your custom fields or workflow are supported.
A worked handoff scenario
Suppose an approved weekly plan recommends 150 units for an item at a warehouse. This is an illustrative example. The payload needs more than the quantity: item and warehouse identifiers, unit of measure, required date, plan version, approval reference, and a unique transfer reference all help prevent ambiguity.
If the receiving system rejects the item code, the plan should show a failed handoff rather than silently report success. When the operator corrects the mapping and retries, the process must avoid creating two equivalent transactions. Agree the duplicate-prevention method and test it deliberately.
Test the failures before rollout
Use a non-production environment when available. Try an unknown item, a closed period, an invalid unit, a missing permission, a timeout, and a repeated transfer. Verify what the operator sees and who receives the exception. A timeout is especially important: the receiving system may have accepted the update even when the sender did not receive its acknowledgement.
Reconcile record counts and quantities, not just transport success. Keep source and destination references together so a reviewer can trace an approved output without searching unrelated logs.
What should stay under human control?
Define the boundaries for changing a forecast, inventory policy, supplier preference, or operational order. Approval rules should follow the consequence of the action. A read-only analytical refresh generally has a different risk from an order update.
For GrepEye Supply Chain, use a walkthrough to confirm your source systems, desired output, approval stages, and integration scope. Bring the forecast pilot data pack. Teams evaluating invoice handoffs instead should use the separate Tally invoice integration checklist, because finance review and accounting posting require a different contract.