Cloudflare Skills is a collection of instructions and tools that help coding agents build on Cloudflare Workers, the Agents SDK, and other Cloudflare developer services. It is for agents and developers using Cloudflare’s platform. The catalogue entries package the project’s guidance as skills, commands, rules, plugins, and MCP tools.
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.
npx skills add cloudflare/skills --skill durable-objectsgit clone --depth 1 https://github.com/cloudflare/skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/cloudflare/skills/durable-objects)<a href="https://agentmods.dev/skills/cloudflare/skills/durable-objects"><img src="https://agentmods.dev/badge/skills/cloudflare/skills/durable-objects/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/cloudflare/skills/durable-objects"><img src="https://agentmods.dev/badge/skills/cloudflare/skills/durable-objects.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00022 | $0.01355 |
| Opus 5.5 | $0.00009 | $0.00542 |
| Sonnet 5.5 | $0.00004 | $0.00271 |
| Haiku 4.5 | $0.00002 | $0.00136 |
Grade A, and why
durable-objects scanned grade A with 1 finding 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 15d 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
async fetch(request: Request, env: Env): Promise<Response> { Copies of this mod
6 near-identical copies found in the catalogue:
- durable-objects — 100% identical, 34 lines differ
- durable-objects — 100% identical, 34 lines differ
- durable-objects — 100% identical, 34 lines differ
- durable-objects — 100% identical, 34 lines differ
- durable-objects — 88% identical, 131 lines differ
- durable-objects — 88% identical, 121 lines differ
How it starts
The opening of the file, as written. The whole thing — 181 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Durable Objects
Build stateful, coordinated applications on Cloudflare's edge using Durable Objects.
Retrieval Sources
Your knowledge of Durable Objects APIs and configuration may be outdated. Prefer retrieval over pre-training for any Durable Objects task.
Fetch the relevant doc page when implementing features.
When to Use
- Creating new Durable Object classes for stateful coordination
- Implementing RPC methods, alarms, or WebSocket handlers
- Reviewing existing DO code for best practices
- Configuring wrangler.jsonc/toml for DO bindings and migrations
- Writing tests with Cloudflare’s Vitest integration
- Designing sharding strategies and parent-child relationships
Reference Documentation
./references/rules.md- Core rules, storage, concurrency, RPC, alarms- Testing reference - Current Vitest documentation, migration choices, and test selection
./references/workers.md- Workers handlers, types, wrangler config, observability
Search: blockConcurrencyWhile, idFromName, getByName, setAlarm, sql.exec
Core Principles
Use Durable Objects For
| Need | Example |
|---|---|
| Coordination | Chat rooms, multiplayer games, collaborative docs |
| Strong consistency | Inventory, booking systems, turn-based games |
| Per-entity storage | Multi-tenant SaaS, per-user data |
| Persistent connections | WebSockets, real-time notifications |
| Scheduled work per entity | Subscription renewals, game timeouts |
Do NOT Use For
What ships with it
3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 15d ago Changed 2468c1795f43
- 24d ago Changed · +5 lines 2f9d7b37273e
- 1mo ago Changed · -11 lines · -54 tokens per session bd2ef83fd539
- 1mo ago First seen · 187 lines · 76 tokens per session scan A cd6797cb18f3
durable-objects is a skill published in the GitHub repository cloudflare/skills (3,079 stars, last pushed yesterday), licensed Apache-2.0. It adds 22 tokens to every session and 1,355 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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