When designing and implementing APIs, always provide comprehensive specifications that clearly document all endpoints, methods, parameters, and expected responses. This should include: 1. **Method and parameter definitions** - Document each endpoint with its HTTP method, required/optional parameters, and parameter types. Example: ``` PUT: /v1/storage/{tenant}/{timeline}/{endpoint}/{path} Parameters: - tenant: string (required) - The tenant identifier - timeline: string (required) - The timeline identifier - endpoint: string (required) - The endpoint identifier - path: string (required) - The relative file path - data: binary (required) - The file content Response: JSON object with status and operation details ``` 2. **Lifecycle states and transitions** - For resources with complex lifecycles, document the possible states (e.g., Active, Deleted) and the API operations that trigger transitions. 3. **Service integration patterns** - When an API is used for service-to-service communication, document which service is responsible for initiating specific operations and how services should interact. 4. **Error responses and handling** - Include possible error codes, their meanings, and recommended client handling strategies. Clear API specifications facilitate integration, prevent misunderstandings, and serve as essential documentation for both API producers and consumers.