Step by step
Give your developer the connector specification from the connection form. The adapter must preserve your existing design, blog routes and content. Static-only sites need a separate agreed publishing workflow.
Use HTTPS and an endpoint on the same origin as the website. Set a dedicated random secret on the website server and in the form. Never put it in public code, logs or screenshots.
The adapter must support persistent images, idempotent delivery and operation-status checks to prevent duplicates after interrupted responses. Save and check access. A test draft requires separate confirmation and writes one non-public item.