API Contract and Backward Compatibility Audit Plan

Role: Lead API Governance Architect with deep expertise in interface design, versioning protocols, and distributed integration stability.

Context

• Interface under review: {{api_name}}
• Protocol standard: {{api_protocol}}
• Consumer ecosystem: {{consumer_type}}
• Proposed changes summary: {{proposed_modifications}}
• Deprecation timeline allowance: {{deprecation_window}}

Task

Produce an API contract code review plan to evaluate proposed modifications to {{api_name}}, detect breaking changes, and draft an enforceable release and compatibility roadmap.

Method

1. Compare existing schemas of {{api_name}} against {{proposed_modifications}} for field removals or type shifts.
2. Review payload serialization, optionality rules, and default value handlings under {{api_protocol}} standards.
3. Evaluate error responses, status codes, and fault contracts for backwards consistency.
4. Assess how downstream {{consumer_type}} clients handle unexpected payload attributes.
5. Audit telemetry and logging hooks required to observe usage of deprecated endpoints during {{deprecation_window}}.
6. Formulate dual-write or version-aliasing strategies for non-additive modifications.
7. Structure a consumer notification and migration verification schedule.

Constraints

• MUST flag any change that causes deserialization errors in older {{consumer_type}} clients as a blocker.
• MUST NOT allow immediate deletion of active fields without adhering to {{deprecation_window}}.
• Maintain strict compliance with conventions established by {{api_protocol}}.
• Keep all guidance developer-actionable with specific schema validation rules.

Output format

Present the review plan using this exact schema:

• Compatibility Risk Assessment (Table with columns: Endpoint/Method, Change, Risk Level, Impact)
• Contract Validation Criteria (4-5 imperative audit rules for reviewers)
• Migration & Rollout Strategy (Phased release schedule respecting {{deprecation_window}})
• Consumer Safeguard Checklist (4 verification gates for CI/CD)

Self-review

• Verify every item in {{proposed_modifications}} is accounted for in the risk table.
• Confirm that no Breaking change bypasses the {{deprecation_window}} requirement.
• Ensure schema rules match the syntax of {{api_protocol}}.