Babysitter contract-test-generator

Generate contract tests for API migrations with consumer-driven contracts and provider verification

install

source · Clone the upstream repo

git clone https://github.com/a5c-ai/babysitter

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/a5c-ai/babysitter "$T" && mkdir -p ~/.claude/skills && cp -r "$T/library/specializations/code-migration-modernization/skills/contract-test-generator" ~/.claude/skills/a5c-ai-babysitter-contract-test-generator && rm -rf "$T"

manifest: library/specializations/code-migration-modernization/skills/contract-test-generator/SKILL.md

Contract Test Generator Skill

Generates contract tests for API migrations, supporting consumer-driven contracts, provider verification, and breaking change detection.

Purpose

Enable API contract testing for:

Consumer contract generation
Provider verification
Schema validation
Breaking change detection
Mock server generation

Capabilities

1. Consumer Contract Generation

Generate from API usage
Extract from tests
Build from specs
Support multiple formats

2. Provider Verification

Verify against contracts
Test all consumers
Check compatibility
Document failures

3. Schema Validation

Validate request schemas
Check response schemas
Verify data types
Enforce constraints

4. Breaking Change Detection

Detect field removals
Find type changes
Identify required additions
Flag compatibility issues

5. Mock Server Generation

Generate from contracts
Support stub responses
Handle scenarios
Enable development isolation

6. Contract Versioning

Track contract versions
Manage compatibility
Support migrations
Document changes

Tool Integrations

Tool	Purpose	Integration Method
Pact	Consumer-driven contracts	CLI
Spring Cloud Contract	Java contracts	CLI
Dredd	API validation	CLI
Prism	Mock server	CLI
WireMock	Mock server	CLI

Output Schema

{
  "generationId": "string",
  "timestamp": "ISO8601",
  "contracts": [
    {
      "consumer": "string",
      "provider": "string",
      "interactions": [
        {
          "description": "string",
          "request": {},
          "response": {}
        }
      ]
    }
  ],
  "verification": {
    "passed": "boolean",
    "results": []
  },
  "artifacts": {
    "contractFiles": [],
    "mockServerConfig": "string"
  }
}

Integration with Migration Processes

api-modernization: Contract verification
monolith-to-microservices: Service contracts

Related Skills

```
openapi-generator
```
: Spec generation
```
api-compatibility-analyzer
```
: Breaking changes

Related Agents

```
regression-detector
```
: Regression prevention
```
cross-team-integrator
```
: Contract coordination