docs: scope performance measurements to concrete needs

.agents/skills/rea-analysis-optimization/SKILL.md

@@ -15,6 +15,11 @@ Follow the checkout's [performance priorities](../../../AGENTS.md#performance),
 workflow, not additional permission to execute targets, publish, or merge.
 Use the current contracts, provider prerequisites, and user authorization.
 
+Reserve performance measurements for changes that target performance or have a
+concrete regression concern. Routine cleanup uses correctness checks and does
+not require this optimization workflow or synthetic benchmarks merely because
+helper calls, imports, or representations change.
+
 Read [the Kuna case study](references/kuna-case-study.md) when selecting a
 reuse strategy or interpreting a benchmark. Its pinned observations illustrate
 tradeoffs; they are not current-provider guarantees or universal speedups.

AGENTS.md

@@ -53,9 +53,12 @@ Optimize in this order:
 3. CPU and memory. Avoid unnecessary work and copies; bound concurrency,
    retained state and serialization growth.
 
-For changes affecting these costs, measure representative completed tasks and
-compare equivalent workflows before and after where available. Report token
-usage, elapsed time, CPU time and peak process-family memory. Separate cold
+Reserve performance measurements for changes that target performance or have a
+concrete regression concern. Routine cleanup uses correctness checks; changes
+to helper calls, imports, or representations alone do not require synthetic
+benchmarks. When measurement is warranted, measure representative completed
+tasks and compare equivalent workflows before and after where available. Report
+token usage, elapsed time, CPU time and peak process-family memory. Separate cold
 and warm runs, label estimates, and state unmeasured costs. Fewer bytes alone
 do not establish fewer tokens or faster analysis.