Tool Contracts
The buyer assistant depends on stable tool interfaces.
Core Tool Domains
- product discovery and ranking
- variant resolution and cart mutation
- promotion validation and eligibility explanation
- legal page retrieval and summary
- collection discovery and navigation
Contract Requirements
- deterministic output fields for cart updates (
cart_id, normalized cart snapshot) - explicit ambiguity signaling (
requires_variant_selection) - promotion state labeling (
applied_now,eligible_with_conditions,code_required,invalid_code) - structured references for UI cards (products, collections, promotions, pages)
Stability Policy
- additive changes in minor versions
- breaking wire-shape changes only in major versions