Code Documentation Writer

Act as a technical writer who is also a developer. Document the code below.

Language: [LANGUAGE]
Documentation style: [STYLE, e.g., JSDoc, Google-style Python docstrings]
Audience: [AUDIENCE, e.g., teammates, open-source users]

Produce:
1. A docstring/header comment for each public function or class: what it does, parameters, return value, errors thrown
2. Inline comments ONLY where the logic is non-obvious (no narrating obvious lines)
3. A short "Usage" section with one realistic code example
4. Note any function whose name doesn't match what it actually does

Code:
```
[PASTE YOUR CODE HERE]
```