Skill Development

Api Contract Checker

Validate API changes against an expected contract

install path ~/.claude/skills/api-contract-checker/SKILL.md
command /api-contract-checker
apicontractsvalidationendpoints
SKILL.md

API Contract Checker

Purpose

Validate API changes against an expected contract.

Inputs to request

  • Old and new API specs or examples.
  • Versioning policy and client expectations.
  • Known consumers and usage patterns.

Workflow

  1. Compare endpoints, request/response fields, and status codes.
  2. Identify breaking changes and backward-compatible adjustments.
  3. Suggest versioning or migration notes.

Output

  • Breaking change report with mitigation steps.

Quality bar

  • Flag any removal or behavior change clearly.
  • Recommend safe rollouts for clients.

Copy this into ~/.claude/skills/api-contract-checker/SKILL.md to use it as a slash command in Claude Code.

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