EmDash is a content management system for creating and managing websites, built with TypeScript and Astro and deployable on Cloudflare or Node.js with SQLite. It is for site owners and developers who want WordPress-like administration, templates, and plugins without PHP or separate hosting.
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 emdash-cms/emdash --skill building-emdash-sitegit clone --depth 1 https://github.com/emdash-cms/emdashWrote 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/emdash-cms/emdash/building-emdash-site)<a href="https://agentmods.dev/skills/emdash-cms/emdash/building-emdash-site"><img src="https://agentmods.dev/badge/skills/emdash-cms/emdash/building-emdash-site/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/emdash-cms/emdash/building-emdash-site"><img src="https://agentmods.dev/badge/skills/emdash-cms/emdash/building-emdash-site.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 | $0.00066 | $0.01662 |
| Opus 5.5 | $0.00026 | $0.00665 |
| Sonnet 5.5 | $0.00013 | $0.00332 |
| Haiku 4.5 | $0.00007 | $0.00166 |
Grade A, and why
building-emdash-site 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 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.
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 — 152 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Building an EmDash Site
EmDash is a CMS built on Astro. It stores schema in the database (not in code), serves content via live content collections, and provides a full admin UI at /_emdash/admin. Sites are standard Astro projects with the emdash integration.
Common Gotchas
These are the things that silently break sites. Know them before you start.
-
Image fields are objects, not strings.
post.data.featured_imageis{ id, src, alt }. Writing<img src={post.data.featured_image} />renders[object Object]. Use<Image image={post.data.featured_image} />from"emdash/ui". -
entry.idvsentry.data.idare different things.entry.idis the slug, prefixed with the locale (en/my-post) for locales whose URLs are prefixed (use in URLs;entry.data.slugis the bare slug).entry.data.idis the database ULID (use forgetEntryTerms,Comments, and other API calls that need the real ID). Mixing them up causes silent empty results. -
Taxonomy names must match the seed exactly. If your seed defines
"name": "category", you must querygetTerm("category", slug)-- not"categories". Wrong name = empty results, no error. -
Register cache hints when Astro's cache is enabled. Content queries return a
cacheHint; pass it toAstro.cache.set(cacheHint). UsegetSiteSettingsWithCacheHint(),getMenuWithCacheHint(),getTaxonomyTermsWithCacheHint(), andgetWidgetAreaWithCacheHint()when a cached route renders those values. -
No
getStaticPathsfor CMS content. EmDash content is dynamic. Pages must be server-rendered (output: "server"inastro.config.mjs).
File Structure
Every EmDash site has these key files:
my-site/
├── astro.config.mjs # Astro config with emdash() integration
├── src/
│ ├── live.config.ts # EmDash loader registration (boilerplate)
│ ├── pages/ # Astro pages (all server-rendered)
│ ├── layouts/ # Layout components
│ └── components/ # Reusable components
├── seed/
│ └── seed.json # Schema + demo content
├── emdash-env.d.ts # Generated types (from `emdash types`)
└── package.json
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.
- 15d ago Changed 87393083e92b
- 22d ago Changed d328c6dc02d6
- 26d ago Changed · +4 lines f356c5ad1595
- 27d ago Changed · +2 lines cfa40fc641e0
- 1mo ago Changed · -4 tokens per session 7f30134f85a4
- 1mo ago First seen · 146 lines · 70 tokens per session scan A e52b866fbe39
building-emdash-site is a skill published in the GitHub repository emdash-cms/emdash (13,868 stars, last pushed today), licensed MIT. It adds 66 tokens to every session and 1,662 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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