A Token Broker Pattern for Agent-to-Tool Access

A small architecture pattern to avoid over-privileged long-lived credentials in agent workflows.

In many agent systems, the biggest risk is not model quality. It is credential scope.

A token broker helps by issuing short-lived, task-scoped credentials per tool invocation.

Core idea

  • Agent requests capability with task context.
  • Policy layer evaluates scope and audience.
  • Broker returns short-lived token with audit metadata.

This model is easier to reason about than embedding static keys in long-running agent workers.