For long-horizon Claude 5 models, explicitly decomposing a job into step-by-step micro-prompts is no longer the optimal control strategy. The model should receive a complete task specification — job, why, guardrails, and exit criteria — and execute end-to-end, because its training encodes the planning and sequencing that older prompt chains were used to add.
Changes where task responsibility sits: the harness/operator should specify goals and constraints rather than prescribe detailed execution steps. Adopting this can reduce interaction overhead and better use model capability, but it raises the cost of a single failed or off-track run.
As foundation models become trained for long-horizon autonomy, the division of labor between prompter/orchestrator and model shifts from 'how to do it' toward 'what complete outcome is wanted and how to recognize done'.
Claude 5 models perform best when given the complete task specification upfront.
They are trained specifically on executing end-to-end tasks.