Error Handling Patterns skill: what it does and how to install it

What it does. Covers exceptions, Result types, error codes, nullable values, recoverable and unrecoverable failures, plus retries, circuit breakers and async errors. It promotes early validation, preserved context, meaningful messages, appropriate logging, resource cleanup and typed errors, with a worked Python example.

When to use it. Applies when implementing features, designing resilient APIs, debugging production issues, improving reliability or building fault-tolerant distributed systems.