Phase 4: Executor / Coder

The executor phase is about surgical execution. By this stage, the architect has already defined the file paths, function signatures, or target artifacts. The agent is no longer making design decisions; it is fulfilling a contract.

The first step is the creation of a plan in the plans directory. This document breaks the execution into atomic phases. Each phase must be small enough to be fully understood within a single context window. This prevents the model from losing track of the original intent as the project grows.

Execution follows a strict loop. The agent reads exactly one phase from the plan and creates or modifies only that scoped work inside the workspace (or artifacts/ folder). It does not look ahead and it does not alter unrelated components. Every phase ends with a mandatory gate check where the agent runs verification steps and stops.

The agent is required to wait for an explicit go signal before moving to the next phase. This is the safeguard against the doom spiral. If the agent makes a mistake in phase two, you catch it before it becomes the foundation for phase three. You remain the director of the execution rather than a spectator to its collapse.