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 fanfan-de/anybox --skill durable-objectsgit clone --depth 1 https://github.com/fanfan-de/anyboxWrote 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/fanfan-de/anybox/durable-objects)<a href="https://agentmods.dev/skills/fanfan-de/anybox/durable-objects"><img src="https://agentmods.dev/badge/skills/fanfan-de/anybox/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/fanfan-de/anybox/durable-objects"><img src="https://agentmods.dev/badge/skills/fanfan-de/anybox/durable-objects.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00076 | $0.01361 |
| Opus 5 | $0.00038 | $0.00681 |
| Sonnet 5 | $0.00015 | $0.00272 |
| Haiku 4.5 | $0.00008 | $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 8d 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> { This is a copy
100% identical to durable-objects — 21 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 187 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.
| Resource | URL |
|---|---|
| Docs | https://developers.cloudflare.com/durable-objects/ |
| API Reference | https://developers.cloudflare.com/durable-objects/api/ |
| Best Practices | https://developers.cloudflare.com/durable-objects/best-practices/ |
| Examples | https://developers.cloudflare.com/durable-objects/examples/ |
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/vitest-pool-workers - Designing sharding strategies and parent-child relationships
Reference Documentation
./references/rules.md- Core rules, storage, concurrency, RPC, alarms./references/testing.md- Vitest setup, unit/integration tests, alarm testing./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
- Stateless request handling (use plain Workers)
- Maximum global distribution needs
- High fan-out independent requests
Quick Reference
Wrangler Configuration
What ships with it
4 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.
- 8d ago First seen · 187 lines · 76 tokens per session scan A cd6797cb18f3
durable-objects is a skill published in the GitHub repository fanfan-de/anybox (57 stars, last pushed 29d ago), licensed MIT. It adds 76 tokens to every session and 1,361 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). It is 100% identical to durable-objects, differing in 21 lines, and is treated as a copy.
Other skills, from other repositories
stripe-projects
Provision SaaS services + sync creds via Stripe Projects.
azure-eventhub-dotnet
Azure Event Hubs SDK for .NET. Use for high-throughput event streaming: sending events (EventHubProducerClient, EventHubBufferedProducerClient), receiving events (EventProcessorClient with checkpointing), partition management, and real-time data ingestion. Triggers: "Event Hubs", "event streaming"…
azure-mgmt-botservice-dotnet
Azure Resource Manager SDK for Bot Service in .NET. Management plane operations for creating and managing Azure Bot resources, channels (Teams, DirectLine, Slack), and connection settings. Triggers: "Bot Service", "BotResource", "Azure Bot", "DirectLine channel", "Teams channel", "bot management .NET", "create bot".
wikipedia
Search and read Wikipedia via x wkp — MediaWiki API, no API key, zero install; query, extract, suggest, and DDG route in one module. Load for wiki, wikipedia, encyclopedia lookup, article summary.
cve
Look up CVE records via x cve — cached, zero-API-key, daily xz TSV. Load for cve, vulnerability id, kev, epss, nvd, cvelist, or security advisory.
django-storages-s3
Use when configuring Django to store static and media files on AWS S3 with django-storages. Invoke when working with the STORAGES setting, S3 buckets, presigned URLs, CloudFront, or boto3-backed file storage in settings.py. Configures the Django 4.2+ STORAGES dict, public/private custom backends, presigned GET/POST…