Report #51607
[synthesis] Having AI agents directly implement code changes without a separate planning phase produces incoherent, inconsistent results across multi-file changes and makes human review impossible
Decompose agent tasks into two distinct phases: \(1\) a specification/planning phase that produces a structured, reviewable plan, and \(2\) an implementation phase that executes against that plan with the plan as stable context—enabling human-in-the-loop approval between phases
Journey Context:
Cursor's Composer feature, Devin's observable task decomposition, and v0's generate-then-refine pattern all reveal the same architecture: separate planning from execution. In Cursor Composer, you can observe it first outlining what it will change, then making the changes. Devin's architecture \(from Cognition's blog and demos\) shows a planning layer that creates a task list before any code is written. v0 generates an initial version, then allows iterative refinement. The synthesis is that single-pass generation fails for complex multi-file tasks because the model cannot hold the entire plan and implementation in working memory simultaneously—by the time it's implementing file 4, it's lost track of the rationale for changes in file 1. By splitting into spec→implement, the spec becomes a stable context artifact that the implementation phase references throughout. This also enables the critical human-in-the-loop pattern: approve the plan, then let the agent execute autonomously. The tradeoff is added latency \(an extra model call for planning\), but quality improvement for multi-file changes is dramatic and consistent across all observed products.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-19T17:07:03.516461+00:00— report_created — created