How an imbalanced stablecoin pool changes swap direction economics

In a stable-asset pool, the direction of a swap can either replenish the scarce asset or make the imbalance larger. The resulting prices depend on the pool's invariant, scaling and fee rules. Equal dollar-target labels do not remove those inventory effects.

Use economically comparable balances

Suppose a hypothetical two-asset pool holds far more value in A than in B. A trader selling A to acquire B removes more of the scarce B. A trader sending B to acquire A moves balances toward the other direction. These requests can face different average rates at matched sizes.

Raw counts alone may mislead when decimals or token exchange-rate scaling differ. Convert to the units the pool's pricing model uses before calling the pool balanced or imbalanced.

Inspect the implemented curve and fee

Curve's technical pool documentation describes amplification as a parameter affecting tolerance for imbalance. It is a curve property, not extra token inventory. A larger parameter does not create an unlimited supply of the scarce asset.

Some pool implementations also make fees depend on imbalance. Do not apply a remembered fixed fee to every stable pool; inspect the actual quote's treatment.

A practical quote comparison

Obtain quotes in both directions at equal initial reference value. Then increase size modestly and observe how average rates change. Preserve the same observation state where possible so a timing change is not mistaken for directional asymmetry.

A favorable rate for replenishing a side does not establish that the replenished token has no market risk or that the imbalance will resolve profitably. This page addresses execution quality only. Report the available rate and the pool assumptions without interpreting an inventory incentive as a guaranteed arbitrage or a prediction that both tokens will return to parity.