AI Systems Atlas

X-14Subagent Context Isolation

/context/subagent-isolation

Delegation as a context move: the subagent spends a fresh window on the search and returns only the answer.

Step-by-step walkthrough7 steps
  1. The parent has a plan and a nearly empty window. It intends to keep it that way.
  2. It needs an answer that costs a lot of reading to find. It delegates the question, not the work.
  3. The subagent opens forty files and burns ninety thousand tokens finding out.
  4. It returns eight hundred tokens: the answer, the files that matter, the traps.
  5. Only the digest crosses back. The parent’s window grew by a paragraph, not by a codebase.
  6. Everything else is discarded with the subagent’s window — which is exactly the point, and also the risk.
  7. What the subagent didn’t write down, the parent can never ask about. Delegation is lossy by construction.
Key insight

Read the org chart as a context diagram. The parent pays for the digest, not the exploration — which is why a subagent is worth it even when a single agent could have done the work.

Failure mode

A digest that omits what the parent didn’t know to ask for. Everything not written down dies with the subagent’s window, and the parent cannot tell the difference between “no traps” and “traps not mentioned”.

Further reading
RelatedHierarchicalResearcher + ImplementerContext budgetAgent handoffs

Elsewhere in the atlas

Harnesses →Security →Evals →Coding Agents →Tools →Ops →