Start with what each system officially supports
Before writing custom code or automating a user interface, check for REST or SOAP APIs, webhooks, scheduled exports, file exchange, database access or other documented interfaces.
Often an integration interface exists even when your workflow platform does not provide a ready-made connector. A small custom connector or service can bridge that gap without automating the screen.
API integration works well when contracts are stable
APIs allow systems to exchange structured data through defined requests and authentication. They usually provide a good foundation for validation, response codes and traceability.
An API integration still needs to account for change. Understand endpoint versioning, rate limits, temporary outages and what should happen when the same business event is delivered more than once.
File exchange can be a perfectly valid architecture
Not every process needs real-time integration. If a system reliably exports CSV, XML, JSON or another structured format, scheduled file exchange can be simpler and more dependable than a complicated direct connection.
The workflow must control format versions, validate required fields and record which items have already been processed. Otherwise rerunning the same file can create duplicates.
Middleware can isolate complexity
When the source and destination use very different data models, a small integration service can transform and validate data while recording every event. It can also reduce dependency on a particular workflow platform.
Middleware can introduce queues, retry policies and idempotency. Those capabilities become important when the integration handles operationally significant data and a temporary failure must not mean lost information.
Use user-interface automation carefully
If there is no API, export or supported data channel, browser or desktop automation may be the remaining option. It can be practical, but it is more fragile because a UI change can break the workflow.
In that situation, monitoring, error logging and a safe way to stop the automation become especially important.
An integration is reliable only when failure is designed as well
Moving data from system A to system B is only half the job. A production integration must also answer what happens when B is unavailable, the data is invalid or the same event is received twice.
Choose the most stable supported interface available and surround it with validation, monitoring and explicit failure handling.