Assign a source of truth
For each field, decide which system owns the correct value. If both systems can change it, define conflict-resolution rules.
An order status and a contact email may have different owners. Copying every field in both directions can overwrite useful updates.
Define events and identifiers
What starts the exchange: creation, confirmation, payment or an update? How do you identify the same object in both systems?
Use stable identifiers. A name or email may change, be duplicated or be missing.
Check retries and ordering
A webhook can arrive more than once, and events can arrive out of order. Define how to recognise an operation already processed or a stale update.
Important operations may need persisted processing state. The design depends on the API, latency requirements and the consequences of repetition.
Plan for errors and limits
Check request quotas, permissions, token expiry and plan restrictions. Decide which errors can be retried automatically.
Invalid data, revoked access and partially completed operations need distinct handling. Endless retries without visibility do not resolve a fault.
Verify the whole outcome
How will you know records stopped synchronising? Who is notified, and how can an operation be replayed? Some workflows need periodic reconciliation.
If AI participates, add quality examples, a cost limit and a human-review rule. A pilot should evaluate the complete workflow, not only the model’s response.