BDD from API Spec

BDD from API Spec Skill

Automatically generate Gherkin feature files from API handler definitions, producing executable business specifications for each endpoint.

Trigger Conditions

• New handler file is created
• Existing handler endpoint is modified
• BDD scenarios are requested
• User invokes with "write BDD" or "bdd-from-api-spec"

Input Contract

• Required: Path to handler files
• Optional: OpenAPI spec for additional context

Output Contract

• Gherkin .feature files per handler/​resource
• Scenario coverage: happy path, error cases, edge cases, auth checks
• Step definition stubs (Go/​Godog format)

Tool Permissions

• Read: Handler files, DTO files, service interfaces, OpenAPI spec
• Write: Feature files in features/ directory, step definition stubs
• Search: Grep for handler methods, route registrations

Execution Steps

1. Extract endpoints: Parse handler files for all endpoint methods with HTTP method and path
2. Identify scenarios: For each endpoint, generate scenarios:
   • Happy path (valid request, successful response)
   • Authentication failure (missing/​invalid token)
   • Authorization failure (wrong user/​scope)
   • Validation failure (invalid input)
   • Business rule failure (e.g., insufficient funds, account frozen)
   • Idempotency (duplicate request returns same result)
3. Generate Gherkin: Write .feature files with Given/​When/​Then format
4. Generate step stubs: Create step definition file stubs for Godog