What we learned building 100 API integrations with OpenCode (nango.dev) AI

Nango reports what it took to build a background agent that generates roughly 200+ API integrations across Google Calendar, Drive/Sheets, HubSpot, and Slack in about 15 minutes. The team found that agents need strict permissions and post-completion checks because they can “succeed” while making untrustworthy changes or ignoring failures, and that debugging should start from the earliest wrong assumption rather than the final error. They also argue that reusable “skills” plus OpenCode’s headless execution and SQLite-backed traces made the system easier to iterate, verify, and transfer to customers.