Borrowing it
Nothing to install: this file belongs to webjsdev/webjs. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/webjsdev/webjs/main/.agents/skills/webjs/SKILL.mdgit clone --depth 1 https://github.com/webjsdev/webjsWrote 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/webjsdev/webjs/webjs)<a href="https://agentmods.dev/skills/webjsdev/webjs/webjs"><img src="https://agentmods.dev/badge/skills/webjsdev/webjs/webjs/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/webjsdev/webjs/webjs"><img src="https://agentmods.dev/badge/skills/webjsdev/webjs/webjs.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- 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 | $0.00067 | $0.06952 |
| Opus 5.5 | $0.00027 | $0.02781 |
| Sonnet 5.5 | $0.00013 | $0.01390 |
| Haiku 4.5 | $0.00007 | $0.00695 |
Grade A, and why
webjs 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 12d 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.
How it starts
The opening of the file, as written. The whole thing — 287 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Build a WebJs App
Use this skill for end-to-end WebJs app work. It helps you choose the right layer first, reach for the right export, and avoid the WebJs-specific mistakes that Next.js or Lit muscle memory causes. WebJs is its own framework: the component API matches Lit and the routing feels like Next, but the execution model is neither.
Full Documentation
This skill is the quick guide. When you need the full API reference for a surface, load the matching file in references/ (listed below). For even deeper framework detail, WebJs ships buildless, so the source you run IS the source you read: look in node_modules/@webjsdev/{core,server,cli}/ (each package ships its own AGENTS.md). To check ONE export's contract, run npx webjs source <Export> (for example npx webjs source createAuth, or --pkg core to narrow): it prints that export's signature and the doc comment above it from the installed package, so you read the declaration instead of the file. The MCP source tool does the same with export. Open the source file when the question is about behaviour the signature does not state. The complete hosted docs live at https://webjs.dev/docs.
What WebJs Is
WebJs is an AI-first, web-components-first framework with no build step: source files are served as native ES modules, and TypeScript is stripped in place (Node 24+ or Bun). It runs SSR + progressive enhancement by default.
There is no server/client component split. No RSC render tree, no Flight protocol, no "use client" boundary. Instead:
- Pages and layouts (
app/**/page.ts,app/**/layout.ts) run only on the server to produce HTML. They do NOT hydrate, so their own markup cannot be interactive (an@clickin a page template is dropped at SSR). They still LOAD in the browser so imported components register. - Components (
WebComponentcustom elements) hydrate per element, islands-style. All interactivity lives here:@event, reactive property assignment, signal mutation. *.server.tsis the one server boundary. With'use server'its exports are RPC-callable from the client (the import is rewritten to a stub); without it the file is a server-only utility whose browser import throws at load. This, not a component annotation, is how a dependency (the DB driver, secrets,node:*) is kept off the client.route.tsis a server-only HTTP handler (namedGET/POSTexports), the one routing file that is NOT isomorphic.
What ships with it
15 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.
- references/auth-and-sessions.md 15 KB
- references/built-ins.md 38 KB
- references/client-router-and-streaming.md 44 KB
- references/components.md 57 KB
- references/data-and-actions.md 29 KB
- references/module-structure.md 11 KB
- references/muscle-memory-gotchas.md 41 KB
- references/optimistic-ui.md 12 KB
- references/routing-and-pages.md 28 KB
- references/runtime.md 18 KB
- references/service-worker.md 7.4 KB
- references/styling.md 33 KB
- references/testing.md 19 KB
- references/typescript.md 15 KB
- references/ui-kit.md 7.7 KB
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.
- 12d ago Changed · -6 lines 60bb760f9f41
- 13d ago Changed 39b7da10d57e
- 1mo ago Changed · +1 lines f524b3e22e8e
- 1mo ago First seen · 292 lines · 67 tokens per session scan A f64cb93bc7ea
webjs is a skill published in the GitHub repository webjsdev/webjs (27 stars, last pushed 13d ago), licensed MIT. It adds 67 tokens to every session and 6,952 once invoked, about $0.0003 per session on Opus 5.5. 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.
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