workers

A set of rules for developing applications on Cloudflare Workers, Cloudflare’s platform for running server code at the network edge.

In plain words
What is it for?
Use it when developing or deploying Workers applications, configuring services such as KV, R2, D1, or Queues, generating types, and diagnosing runtime or resource-limit errors.
Why use it?
It tells the agent to check current Cloudflare documentation for APIs, limits, and deployment details that may change over time.

Cursor rule

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/cloudflare/skills/workers
Clone the repo
git clone --depth 1 https://github.com/cloudflare/skills
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 459 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00459
Opus 5 $0.00000 $0.00230
Sonnet 5 $0.00000 $0.00092
Haiku 4.5 $0.00000 $0.00046

Measured 2d ago against content hash b5443d6c57c0, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

workers scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

rules/workers.mdc · 61 lines

What it actually says

Cloudflare Workers

STOP. Your knowledge of Cloudflare Workers APIs and limits may be outdated. Always retrieve current documentation before any Workers, KV, R2, D1, Durable Objects, Queues, Vectorize, AI, or Agents SDK task.

Docs

For all limits and quotas, retrieve from the product's /platform/limits/ page.

Commands

Command Purpose
npx wrangler dev Local development
npx wrangler deploy Deploy to Cloudflare
npx wrangler types Generate TypeScript types

Run wrangler types after changing bindings in wrangler.jsonc.

Node.js Compatibility

If you encounter Dynamic require of "X" is not supported or missing Node.js APIs:

{
  "compatibility_flags": ["nodejs_compat"],
  "compatibility_date": "YYYY-MM-DD" // Use today's date
}

Docs: https://developers.cloudflare.com/workers/runtime-apis/nodejs/

Errors

Product Docs

Retrieve API references and limits from: /kv/ · /r2/ · /d1/ · /durable-objects/ · /queues/ · /vectorize/ · /workers-ai/ · /agents/

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 61 lines · 0 tokens per session scan A b5443d6c57c0

Subscribe to this mod's changes

workers is a cursor rule published in the GitHub repository cloudflare/skills (2,744 stars, last pushed 25d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 459 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.