Leave a reference document instead of a conversation
In AI coding, the longer a conversation runs, the easier it is to lose track of what has been settled. SPECS.md keeps product requirements and completion criteria in one place, so a new session or a different agent works from the same standard.
Don't mix the spec and the implementation in one step
GitHub Spec Kit's basic flow separates Spec, Plan, Tasks, and Implement. Each output becomes the input to the next step, so it is easier to find missing constraints and tests before implementation starts.
Documents are also subject to change
If requirements change and only the code changes, the earlier assumptions come back to life in the next task. Reflect the reason for the change and its scope of impact in the spec, plan, and task list together, and check them against the actual implementation.
Official resource: GitHub Spec Kit