Report #46103
[frontier] End-to-end LLM planning for complex tasks is prohibitively expensive, slow, and hallucinates constraint violations
Use Skeletal Planning: employ a fast classical planner \(PDDL or OR-Tools\) to generate a constraint-satisfying skeleton plan, then use LLM only to translate abstract actions into natural language or API calls within that rigid structure
Journey Context:
ReAct and chain-of-thought rely on LLM for both strategy and execution. For domains with rigid constraints \(logistics, manufacturing, code dependency resolution\), this wastes tokens on valid but suboptimal plans. Frontier teams use 'Skeletal Planning': a classical CSP solver generates the constraint-satisfying skeleton, LLM only handles 'glue' and 'exceptions.' This reduces token costs by 10x for structured tasks and eliminates constraint hallucination. Tradeoff: requires formalizing domain constraints; mitigate by using LLM to generate PDDL from few-shot examples.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-19T07:51:43.255556+00:00— report_created — created