Contract Rules

Status: Canonical
Last updated: 2026-07-05

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Principles

1. One primary *PlatformContract per platform — consumers import contracts package only
2. Methods return DTOs — never Eloquent models across boundaries
3. Versioned packages — contracts@N semver; breaking changes require ADR
4. Registry ownership — metadata in zaixos-registry, not duplicated in consumers

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Consumer pattern

sequenceDiagram
    participant M as Product Module
    participant C as PlatformContract
    participant A as Platform Adapter
    M->>C: invoke(DTO)
    C->>A: delegate
    A-->>M: ResponseDTO

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Product contracts

Products may expose product contracts for federation (e.g. Agent Operations export). These live in product or packages/contracts and are indexed in REFERENCE/contracts-index.md.

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Related

• dto-rules.md
• adapter-rules.md
• API/README.md
• ADR/ADR-003-runtime-contracts.md

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