“We have a warehouse system and a store, and we want them connected.” That is a useful opening, but not enough to estimate the integration. Will only inventory move, or orders, customers and returns too? Who owns prices? What happens if a product changes in both systems at once? Those answers shape the work more than the number of system names.
This brief helps you prepare a request for an API integration company without writing a detailed software specification. Its purpose is to describe the outcome and expose dependencies early. A supplier does not need production keys or a full copy of customer information simply to identify what needs investigation.
Choose one representative data journey
Consider a fictional clothing retailer. Its ERP manages item records and inventory, while the online store receives orders. Confirmed orders are transferred, and cancellations or returns may require further updates. Define the beginning and end rather than requesting an undefined “complete synchronization.”
Ask the team about today's manual work: who exports a file, edits it, imports it and discovers a missing record? The problem may be mismatched product codes, delayed updates or missing review ownership. Integration must address the cause you describe, not merely move the old file faster.
Identify each field's owner and direction
| Information | Responsible source in the example | Direction and decision |
|---|---|---|
| Product and variant code | ERP | Sent to the store, with rules for matching existing codes. |
| Available inventory | The agreed inventory system | Updated according to agreed locations, reservation rules and timing. |
| Online order | Store | Transferred after the business-approved event with a stable reference. |
| Preparation status | The fulfillment operation | Returned to the store if included in scope. |
| Cancellation and return | The agreed process for each case | Decision ownership and downstream effects defined before coding. |
This is an example rather than a rule for every business. If online prices are independent of ERP prices, say so. Avoid allowing both systems to change a field without a conflict rule. Bidirectional synchronization can require extra decisions rather than simply enabling two arrows.
An API does not prove your required operation is available
Request documentation for the actual versions, available operations and account or plan limitations. A system may allow reading a product without allowing a particular update in the way you need. Access may depend on provider approval, a license or a test environment you do not yet have.
Record dependencies: who requests access, supplies sample data and answers third-party questions? Do not base a project timeline on an external approval without documenting the effect of delay. If an initial technical feasibility study is needed, agree on the evidence that will establish whether the connection is possible and where its limits lie.
Choose timing that serves the operation
Must an update arrive within moments, or will scheduled batches work for nonurgent data? Different fields can need different answers. Delayed stock for a fast-selling item is not equivalent to a delayed internal report reviewed the next morning. Explain the business effect, then ask the implementer to propose a suitable method and its limits.
Shopify documentation describes webhooks as a way to receive near-real-time event information rather than repeatedly asking for changes. That is a useful technical example, not evidence that every system exposes the same event. Verify both sides' mechanisms and how missed updates will be reconciled.
Describe failure before accepting the success path
In the fictional retailer, the ERP may accept an order while the connection fails before confirmation reaches the store. If the order is sent again, how does the receiver recognize it? Some interfaces support keys that prevent unintended repeated actions, as Stripe explains for idempotent requests. Details and limits depend on the interface used.
As a buyer, request clear rules for references, retries, unresolved states and manual reprocessing. Ask how missing records or mismatched stock are detected even when no connection error is logged. A successful connection and a correct business outcome are different things.
Prepare representative samples without unnecessary disclosure
Provide field structures and fictional samples representing products, variants, orders and returns, including incomplete or unusual cases. Explain currencies, units, dates and time zones without inserting real prices or customer information merely because they are available.
When authorized implementation begins, agree on dedicated accounts, suitable permissions and a secure handoff route for sensitive information. Do not place access keys in a request-for-proposal document or a message shared with unrelated parties. Ask about the test environment and its limits compared with production.
Request deliverables you can test and operate
The proposal should explain data and event mapping, failure handling, acceptance tests, monitoring records, documentation and support ownership. Name the systems, interfaces and flows included instead of using broad language that can expand into undiscussed functions.
- Test valid, incomplete and repeated records against agreed rules.
- Test delayed responses or an unavailable system and inspect the operator's view.
- Reconcile a sample between source and destination and explain exceptions.
- Try an update after a data change, plus cancellation or return when included.
- Identify the acceptance owner and the person following alerts after handover.
Separate initial development from hosting, operations and later API-version changes. A connected system may change months later. Know who detects that change, tests its effect and handles it under the support agreement.
For the broader picture, read the ERP, CRM and e-commerce integration guide. When discussing system integration services, send your reference journey, data-ownership table and dependencies. A good brief does not replace technical analysis. It focuses that analysis on a problem that can be estimated and whose solution can be verified.
Sources
Shopify's webhook introduction and Stripe's idempotent-request documentation were checked on 3 November 2026. Specific concepts are summarized briefly without assuming equivalent provider interfaces or payment-service availability in any country. The example, brief and tests are original proposals. This text was prepared with AI assistance and review of its content and sources.
