error handling
**Error handling** in AI and software systems is the practice of **detecting, managing, and recovering from** failures and exceptions gracefully, ensuring the system remains stable and provides useful feedback rather than crashing or producing silently wrong results.
**Error Categories in AI Systems**
- **API Errors**: Rate limits (429), server errors (500/503), authentication failures (401/403), timeout errors. These require **retry logic** with backoff.
- **Model Errors**: Hallucinations, refusals, empty responses, format violations, or truncated outputs. These require **validation and retry** with modified prompts.
- **Infrastructure Errors**: Network failures, disk full, out-of-memory (OOM), GPU errors. These require **resource monitoring** and fallback strategies.
- **Data Errors**: Invalid input, missing fields, encoding issues, schema violations. These require **input validation** before processing.
**Best Practices**
- **Catch Specific Exceptions**: Handle each error type with appropriate recovery logic rather than catching all exceptions generically.
- **Don't Swallow Errors**: Always log or report errors — silently ignored exceptions are the hardest bugs to diagnose.
- **Use Structured Error Responses**: Return consistent error objects with error code, message, and suggested action.
- **Fail Fast**: Detect errors early (validate inputs upfront) rather than failing deep in the processing pipeline.
- **Idempotent Recovery**: Ensure retry and recovery operations are safe to repeat without side effects.
**AI-Specific Error Handling**
- **Output Validation**: Check model responses for expected format, length, and content before returning to the user.
- **Guardrail Enforcement**: Catch and handle safety filter activations, content policy violations, and refusals.
- **Token Limit Handling**: Detect context window overflow and implement strategies like truncation, summarization, or chunking.
- **Streaming Error Recovery**: For streaming LLM responses, handle mid-stream disconnections and partial responses.
**Monitoring and Alerting**
- **Error Rate Tracking**: Monitor error rates by type and trigger alerts when thresholds are exceeded.
- **Error Budget**: Define acceptable error rates (SLOs) and take action when the error budget is depleted.
Robust error handling is what separates **demo-quality** AI applications from **production-grade** ones — every edge case not handled is a potential user-facing failure.