Planner Pattern — Problem

Pattern: Planner
Component: problem.md
Version: 1.1 | Updated: 2026-07-16

---

Statement

Complex tasks given directly to coding agents without an explicit plan produce outputs that are token-level correct but architecturally wrong: missed dependencies, inconsistent interfaces, unplanned schema changes, and 2–3× rework.

Measurable symptoms

Symptom	How you detect it
Rework rate	>30% of agent-generated multi-file changes need a second architectural pass
Surprise files	PR touches files not listed in any plan
Interface drift	Coder invents API shapes or table columns not reviewed by a human
Rollback vacuum	Change ships with no documented revert path

Root cause

Agents optimize next-token correctness inside a local context window. Holistic task correctness (ordering, contracts, blast radius) is not enforced unless it is externalized as a reviewed plan.

Non-goals of this pattern

• Not a substitute for a product requirements document
• Not a place to dump implementation code
• Not required for single-file typos, config toggles, or docs-only edits

Related failure modes

See failures.md for recovery when plans are too vague, too detailed, or rubber-stamped.