Replace Parameter with Query

Removes smells

Symptom

A function takes parameters its callers computed from data the function already has access to; the agent verifying any call must reproduce the caller's computation.

Goal

The function computes its own answer; the agent calls it without pre-computing the inputs.

Before the refactoring

const basePrice = order.qty * order.itemPrice;
const level = discountLevel(order);
const final = discounted(order, basePrice, level);

After the refactoring

const final = discounted(order); // computes basePrice and level itself

Example source: Illustrative example written for this site, not a quotation from any source.

Pressure

Every caller pays the homework cost; the duplication of derivation logic scatters and the agent must keep callers in sync with the function's expectations.

Tradeoff

If the query is expensive or has side effects, replacing the parameter multiplies cost or introduces hidden coupling the agent must reason about.

Relief

Signatures shrink; the agent calls the function directly without reproducing caller-side derivations.

Trap

Replacing parameters with queries that are expensive or have side effects multiplies cost or introduces hidden coupling the agent reads as 'just a parameter swap'.