API Contract Tester vs ContractCase
API Contract Tester
clinetools.com
ContractCase
case.contract-testing.ioSide by side
| Figure | API Contract Tester | ContractCase |
|---|---|---|
| Price from | $19/mo | — |
| Free plan | Yes | — |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | — |
| API | — | Yes |
| Plans published | 4 | 0 |
| Spec score · Contract Testing Tools | 8.2 (#7) | 7.5 (#17) |
| Purpose | API Contract Tester verifies frontend-backend API contracts and detects schema mismatches, missing fields, and type incompatibilities. | ContractCase is a consumer-driven contract testing framework for checking whether services can communicate as expected. |
Plans
API Contract Tester
- FreeFree
- Individual Dev$19 a month
- Pro AI Agent$49 a month
- Enterprise$499 a month
In their own words
API Contract Tester
API Contract Tester is a web tool for checking whether frontend and backend APIs follow the same contract. It compares an expected TypeScript, OpenAPI, or JSON schema with actual API responses and identifies missing fields, extra fields, incompatible types, and null violations. Validation covers nested objects, arrays, enums, and optional fields, with mismatch reports that include suggested fixes. You can paste a schema and response into the online interface or run the tool locally as an MCP server. Installation uses `npx @clinetools/contract-test` and requires Node.js 18 or newer. The first CLI run asks about contract strictness and fields to ignore. Setup instructions support Cline and Claude Code, and contract checks can run in deployment pipelines before a frontend release. The free plan costs nothing, billed forever, and includes 100 executions per month; premium modules are excluded. Individual Dev costs $19 a month.
ContractCase
ContractCase has no write-up on Specifiction yet; its figures are above.