API Key and Auth Patterns for Search APIs
Common authentication schemes for search APIs and how to manage keys safely in agent code.
What it means
Most search APIs authenticate with a single static API key passed as a query parameter or header, a simpler scheme than the OAuth flows common in other API categories — which is convenient for quick integration but means the key itself is the entire security boundary, and leaking it (in client-side code, a public repo, or agent logs) grants full account access.
In practice
An agent's search tool wrapper should read its API key from an environment variable or secrets manager, never hardcode it in a prompt template or log it alongside the query text for debugging — a surprisingly common mistake is logging the full outgoing request URL for debugging, which includes the key if it's passed as a query parameter rather than a header.
Tradeoffs
A single static key is simple to integrate but offers no fine-grained scoping — you typically can't issue a key limited to read-only search with a spending cap the way you might with a more granular auth system, so key rotation and spend alerts on the provider dashboard become the practical substitute for scoped permissions.