Resources
What we are building, and what we have learned building it.
Subagents are the feature that demos best and costs most. Nine files audited in parallel looks like magic in a screen recording, and every one of those nine is a full model loop billed to you.
Your domain knowledge has exactly one home, and it is loaded on every turn whether relevant or not. So it grows. Every behaviour change becomes a global change, and eventually nobody can edit what the agent does without touching the one string everything else depends on.
The tool was called cancelbooking. Its description read: "Cancel a booking. Irreversible: the slot is released to the market immediately." The project granted approvals. There was an onApproval handler that refused everything. It was never once consulted.