Primitive of the day · 2026-11-04

plan-constraint-check-upfront

Check hard constraints (data availability, authorization, budget, deadlines) BEFORE executing a plan - a late-invalidated plan is wasted work and mid-execution replanning is expensive.

When this applies

An agent decomposes a goal into a dependency-ordered plan about to be executed.

Preconditions

• A multi-step plan exists before execution starts
• External constraints could invalidate steps

Do this

Enumerate constraints up front (data available? authorized? within budget? deadline feasible?) and validate the plan against them before step 1 runs; plan deeply once rather than editing mid-flight.

What you should see

Plans rarely die mid-execution from foreseeable constraint violations.

How it fails if ignored

A plan invalidated at step k wastes all prior work; mid-execution replanning costs more than upfront checks.

Do not use when

NOT for trivial single-step tasks; NOT about re-checking every step during execution (that is monitoring).

Kind: discipline. Part of the skill Agentic design pattern selector. Free to reuse in your own agent skills.