# Reviewing AI-Generated JavaScript Code

> Review AI-generated JavaScript by verifying runtime assumptions, async boundaries, mutations, and package APIs against the actual application contract and tests.

- Canonical HTML: [https://unrust.dev/languages/javascript/reviewing-ai-generated-code](https://unrust.dev/languages/javascript/reviewing-ai-generated-code)
- Markdown representation: [https://unrust.dev/languages/javascript/reviewing-ai-generated-code/index.md](https://unrust.dev/languages/javascript/reviewing-ai-generated-code/index.md)

Published: 2026-07-14

## Direct answer

Review AI-generated JavaScript by checking what the code will do at runtime, not only whether it parses or resembles a familiar snippet. Inspect data validation, truthiness, mutable references, promise rejection paths, and the installed API surface. Generated JavaScript can look concise while relying on a missing method, swallowing an error, or mutating an object that another caller still owns.

## Review runtime assumptions with concrete values

Types may be absent or broad in JavaScript, so test the values that matter: missing fields, false and zero, malformed input, and rejected promises. Check each boundary against the caller's contract instead of accepting a generic fallback that silently changes what downstream code observes.

## Inspect async failure and cleanup paths

A generated happy-path await can conceal an unhandled rejection, duplicate request, stale state update, or missing cleanup action. Trace what happens when the external operation fails, resolves late, or is cancelled, then add focused evidence proportional to the consequence of getting that path wrong.

## Original example

### Question an unvalidated request body before using it

```javascript
const body = JSON.parse(request.body);
const accountId = body.accountId;
await loadAccount(accountId);
```

This original JavaScript example is deliberately small so the review questions remain visible: is request.body always a string, what happens when parsing fails, what shape does accountId require, and who handles a rejected load? The correct implementation depends on the application's request and error contract, not on a generic generated pattern.

## Checklist

- What runtime values can cross this JavaScript boundary?
- Who owns rejected promises, cancellation, and cleanup?
- Does the installed package actually expose the imported API and signature?

## Practice loop

1. Run an AI-suggested JavaScript change with missing, falsy, and malformed inputs when they are relevant.
2. Verify that every promise rejection and cleanup path has an intentional owner.
3. Confirm imports and method signatures against the installed package version before merging.

## Limits of this page

Runtime checks should be scaled to the risk of the change and cannot cover every browser, deployment, or dependency interaction. A single review exercise cannot establish that AI or any tool caused a result, nor can it distinguish unfamiliar project context from a durable skill issue.

## Source context

Editorially reviewed for Unrust using public language documentation, common code-review practice, and small original examples written for this resource system.

## Related resources

- [How to Review AI-Generated Code Safely](https://unrust.dev/use-cases/review-ai-generated-code/index.md): Use a contract-first review loop to inspect AI-generated code, test risky boundaries, and decide whether a proposed change is ready to merge.
- [How to Spot Hallucinated APIs in Code](https://unrust.dev/use-cases/spot-hallucinated-apis/index.md): Find invented or mismatched APIs in proposed code by checking imports, installed versions, signatures, and failure behavior instead of trusting familiar names.

Next step: [Take the free diagnostic](https://unrust.dev/diagnostic/index.md)