← Index 2026-04-29 / Systems / 7 min read

Context Is the Interface

When the prompt disappears, the environment starts speaking.

A good agent loop is less a prompt and more a room arranged for the right work.

Context design is interface design. The user may never see the retrieved note, the policy, or the hidden checklist, but the system's behavior is shaped by that arrangement.

A narrow context window forces judgment. What enters the room gets power, and what stays outside becomes invisible.

The practical question is no longer how much to include. It is what deserves to be close at hand for this decision.

Routing note

task
memory
policy
reply
const context = await gather({
  task,
  userState,
  projectMemory,
  recentFailures,
});

const response = await agent.run({
  task,
  context: rankByDecisionValue(context),
  guardrails: policy.for(task),
});