What is an API Integration?

Integration work covers authentication (getting and refreshing credentials to call the other system), data mapping (translating one system's data shape into the format the other expects), and handling the practical realities of a live connection — rate limits, pagination, partial failures, and what happens when the remote API is temporarily down. The hard part of integration is rarely the happy path; it's the edge cases. A record might already exist and need updating instead of creating, a field might be optional in one system but required in another, and a token might expire mid-operation and need a transparent refresh. Robust integrations are built assuming these failure modes will happen regularly, not as rare exceptions. For AI agent platforms, integrations are what let an agent actually act in the world rather than just talk about acting — each connected provider (email, calendar, CRM, docs) becomes a capability the agent can invoke, bounded by whatever scopes and permissions the integration was granted.