The most fragile integrations are usually the ones that began as a quick connection. A short checklist can prevent expensive surprises later.
Clarify source of truth.
For every record type, decide which system owns the data. Without this, synchronization creates duplicate updates, conflicting records, and unclear support responsibility.
Confirm authentication and access.
Document credential type, token lifetime, scopes, rate limits, IP restrictions, vendor permissions, and how secrets will be stored and rotated.
Design failure behavior.
Retries, idempotency, partial failures, dead-letter handling, and clear error messages are not extras. They are what make an integration supportable.
Plan observability.
The team needs logs, identifiers, timestamps, and status views that explain what happened when a sync fails or data looks wrong.
Write the support notes.
Good integration documentation names the systems involved, data fields, schedules, error paths, contacts, and safe manual recovery steps.