workers-best-practices
Cloudflare Workers code review and authoring against production best practices.
- Retrieves latest Workers APIs, types, and wrangler configuration schema before reviewing or writing code; biases towards live documentation over pre-trained knowledge
- Covers 40+ best practice rules across configuration, request/response handling, architecture, observability, code patterns, and security
- Flags 15+ common anti-patterns including unbounded streaming, floating promises, global request state, hardcoded secrets, and unsafe crypto usage
- Provides structured review workflow: retrieve references, validate types and config, check patterns and security, validate with tools
Your knowledge of Cloudflare Workers APIs, types, and configuration may be outdated. Prefer retrieval over pre-training for any Workers code task — writing or reviewing.
Retrieval Sources
Fetch the latest versions before writing or reviewing Workers code. Do not rely on baked-in knowledge for API signatures, config fields, or binding shapes.
| Source | How to retrieve | Use for |
|---|---|---|
| Workers best practices | Fetch https://developers.cloudflare.com/workers/best-practices/workers-best-practices/ |
Canonical rules, patterns, anti-patterns |
| Workers types | See references/review.md for retrieval steps |
API signatures, handler types, binding types |
| Wrangler config schema | node_modules/wrangler/config-schema.json |
Config fields, binding shapes, allowed values |
| Cloudflare docs | Search tool or https://developers.cloudflare.com/workers/ |
API reference, compatibility dates/flags |
FIRST: Fetch Latest References
Before reviewing or writing Workers code, retrieve the current best practices page and relevant type definitions. If the project's node_modules has an older version, prefer the latest published version.
# Fetch latest workers types
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